All Single Spring Seals
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961 Mechanical Seal (PS-961) — 5/8″
961 Mechanical Seal (PS-961) — 5/8″
Mechanical Seal 961 — T-6A (5/8″) | PS-961 Equivalent
Equal to industry standard 961 / PS-961.
Direct-fit T-6A single-spring seal for pool/spa and small-pump applications—built with a machined carbon face for smoother sealing and longer life in everyday service.At-a-glance: 5/8″ shaft • 1.25″ × 0.406″ cup seat • Machined carbon/ceramic faces • Buna-N elastomers
Why choose 961 (PS-961)
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T-6A footprint for quick, drop-in replacement
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Machined carbon vs. molded carbon for improved surface finish and stability
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Dependable Buna-N for standard pool/spa chemistry
Upgrades / Variations (same footprint)
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1000 — Basic
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3865 — Premium + Viton
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1000cv— Molded carbon
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1000cvss — Silicon Carbide / Silicon Carbide / Viton
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Pre-Cut Gaskets.
Have questions? Check out our Pool/Spa Small Pump Guide or call us anytime—we’re here to help
Please click “specifications for OEM numbers and Nameplate Data
978c Mechanical Seal (PS-978) – 1-1/4″
978c Mechanical Seal (PS-978) – 1-1/4″
Item #N/A
Single Spring Mechanical Seal 978C — 1-1/4″ | PS-978 Equivalent
978c single spring mechanical seal, PS-978 / 978 equivalent. Fits 1-1/4″ shaft with 1.765″×.365″ seat and Type N-33 (tapered spring) rotary head.
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 1-1/4″ single spring seal • Seat: 1.765″ x 0.365″ • Rotary OD: 1.787″ • Working length: 1.062″
Design & construction:
Crimped rotary head (Type N-33)—equivalent to Pac-Seal T-21 (tapered spring) and Burgmann MG9, can replace seal type D & 2 type seal heads. Tapered spring for wide base to fit over impeller hub or other similar feature. Electro-polished 304 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).
Materials available (choose from dropdown)
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CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
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CAR/CER/VIT — Carbon vs. Ceramic faces, Viton elastomers
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SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton elastomers
Have questions? Check out our Single Spring Seal Guide or call us anytime—we’re here to help.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
Please click “specifications” below for OEM numbers and Pump Nameplate Data
MG1 G4 Mechanical Seal – 25mm
MG1 G4 Mechanical Seal – 25mm
MG1 G4 Mechanical Seal (T-19) – 25mm
Direct-fit aftermarket MG1 G4 25mm mechanical seal replacement seal built for demanding pump applications where extended wear life and chemical resistance matter. This version uses a Viton elastomer with Silicon Carbide / Silicon Carbide (SiC/SiC) sealing faces, making it an excellent choice for tough water conditions, higher heat, and abrasive service compared to standard carbon/ceramic combinations.
Specifications
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Seal Style: MG1 G4
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Shaft Size: 25mm
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Seat Size: 38mm × 7.5mm
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Elastomer: Viton (FKM)
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Face Materials: Silicon Carbide / Silicon Carbide
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Cross Reference: T-19, HD-8038, STG4VSC25
Cross references & alternative part numbers
This seal is also commonly referenced as:-
T-19 25mm mechanical seal
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HD-8038 seal
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STG4VSC25 seal
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MG1 25mm Viton SiC/SiC seal
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25mm mechanical seal with 38 × 7.5mm seat
Need help confirming fit?
If you’re matching a seal by size, confirm the shaft size (25mm) and the seat (38 × 7.5mm) before ordering. If you want, send us the pump model and a photo of the old seal/seat for verification.
SPS-205 Mechanical Seal (PS-205) – 1-3/4″
SPS-205 Mechanical Seal (PS-205) – 1-3/4″
Item #N/A
Single Spring Mechanical Seal SPS-205 | PS-205 Equivalent
SPS-205 single spring mechanical seal, equivalent to industry standard PS-205 / 205. Fits 1-3/4″ shaft with 2.500″×0.500″ seat and Type E/1 rotary head.
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 1-3/4″ single spring seal • Seat: 2.500″ x 0.500″ • Rotary OD: 2.402″ • Working length: 2.000″
Design & construction:
Rotary head Type E/1. Electro-polished 316 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).
Materials available (choose from dropdown)
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CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
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CAR/CER/VIT — Carbon vs. Ceramic faces, Viton/FKM elastomers
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SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton/FKM elastomers
Please click “specifications” below for OEM numbers and Pump Nameplate Data
Both PS replacements? Which should I choose? Check out more on our Seal House Seal Guide
Seal Model Product Line Replaces Features & Focus 205C N Line PS-205 Easy installation & broad compatibility SPS-205 SPS Line PS-205 Premium build for longevity & like for like replacement.
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
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Heavier elastomer bellows for improved structural integrity and stability under pressure
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Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
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316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
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Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
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Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
SPS-278 Mechanical Seal (PS-278 Cup) – 2-3/8″
SPS-278 Mechanical Seal (PS-278 Cup) – 2-3/8″
Item #N/A
Single Spring Mechanical Seal SPS-278 | PS-278 cup Equivalent
SPS-278 is a single spring mechanical seal equal to industry standard 278 / PS-278 cup.
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 2-3/8″ single spring seal • Seat: 3.250″ x .562″ cup • Rotary OD: 3.083″ • Working length: 2.500″
Design & construction:
Rotary head Type E/1. Electro-polished 316 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).
Materials available (choose from dropdown)
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CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
-
CAR/CER/VIT — Carbon vs. Ceramic faces, Viton/FKM elastomers
-
SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton/FKM elastomers
Please click “specifications” below for OEM numbers and Pump Nameplate Data
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
-
Heavier elastomer bellows for improved structural integrity and stability under pressure
-
Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
-
316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
-
Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
-
Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
SPS-279 Mechanical Seal (PS-279 Cup) – 2-1/2″
SPS-279 Mechanical Seal (PS-279 Cup) – 2-1/2″
Item #N/A
Single Spring Mechanical Seal SPS-279 | PS-279 cup Equivalent
SPS-279 is a single spring mechanical seal equal to industry standard 279 / PS-279 cup
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 2-1/2″ single spring seal • Seat: 3.375″ x .562″ cup • Rotary OD: 3.210″ • Working length: 2.500″
Design & construction:
Rotary head Type E/1. Electro-polished 316 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).
Materials available (choose from dropdown)
-
CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
-
CAR/CER/VIT — Carbon vs. Ceramic faces, Viton/FKM elastomers
-
SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton/FKM elastomers
Please click “specifications” below for OEM numbers and Pump Nameplate Data
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
-
Heavier elastomer bellows for improved structural integrity and stability under pressure
-
Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
-
316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
-
Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
-
Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
SPS-3025 Mechanical Seal (PS-3025) – 1-5/8″
SPS-3025 Mechanical Seal (PS-3025) – 1-5/8″
Single Spring Mechanical Seal SPS-3025 | PS-3025 Equivalent
SPS-3025 single spring mechanical seal, PS-3025 / 3025 equivalent. Fits 1-5/8″ shaft with 2.375″×0.500″ seat and Type D/2 rotary head
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 1-5/8″ single spring seal • Seat: 2.375″ x 0.500″ • Rotary OD: 2.636″ • Working length: 1.375″
Design & construction:
Rotary head Type D/2. Electro-polished 304 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).Material: CAR/SIC/EPDM — Carbon vs. Silicon Carbide, EPDM elastomers
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
-
Heavier elastomer bellows for improved structural integrity and stability under pressure
-
Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
-
316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
-
Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
-
Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
SPS-323 Mechanical Seal (PS-323) – 2-1/4″
SPS-323 Mechanical Seal (PS-323) – 2-1/4″
Item #N/A
Single Spring Mechanical Seal SPS-323 | PS-323 Equivalent
323c single spring mechanical seal, PS-323 / 323 equivalent. Fits 2-1/4″ shaft with 3.125″× 0.562″ seat and rotary head Type E/1
Shaft size: 2-1/4″ • Seat: 3.125″ × 0.562″ cup • Rotary OD: 3.150″ • Working length: 2.375″
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Design & construction:
Rotary head Type E/1. Electro-polished 316 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation)
Materials available
-
CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
-
SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton/FKM elastomers
Both PS replacements? Which should I choose? Check out more on our Seal House Seal Guide
Seal Model Product Line Replaces Features & Focus 323C N Line PS-514 Easy installation & broad compatibility SPS-323 SPS Line PS-514 Premium build for longevity & like for like replacement.
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
-
Heavier elastomer bellows for improved structural integrity and stability under pressure
-
Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
-
316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
-
Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
-
Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
Please click “specifications” below for OEM numbers and Pump Nameplate Data
SPS-324 Mechanical Seal (PS-324 Cup) – 3″
SPS-324 Mechanical Seal (PS-324 Cup) – 3″
Item #N/A
Single Spring Mechanical Seal SPS-324 | PS-324 cup Equivalent
SPS-324 single spring mechanical seal, PS-324 / 324 cup equivalent. Fits 3″ shaft with 3.875″×.625″ seat and Type E/1 rotary head.
Typical applications: Centrifugal pumps, mixers, and other rotating equipment.
Key specs: Shaft size: 3″ single spring seal • Seat: 3.875″ x .625″ cup • Rotary OD: 3.770″ • Working length: 2.875″
Design & construction:
Rotary head Type E/1. Electro-polished 316 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).
Materials available (choose from dropdown)
-
CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile elastomers
-
CAR/CER/VIT — Carbon vs. Ceramic faces, Viton/FKM elastomers
-
SIC/SIC/VIT — Silicon Carbide vs. Silicon Carbide faces, Viton/FKM elastomers
Please click “specifications” below for OEM numbers and Pump Nameplate Data
SPS Line
Same Fit. Lasting Reliability.
Our SPS single-spring seals are like-for-like replacements for industry-standard E/1, D/2, and C/21 heads—delivering the same fit and function with upgraded materials designed for extended service life.
What sets SPS apart:
-
Heavier elastomer bellows for improved structural integrity and stability under pressure
-
Resin-impregnated, abrasion-resistant carbon faces — double-density carbon designed for enhanced hardness and durability
-
316/304 stainless steel components for superior corrosion protection across E/1, D/2, and C/21 head styles
-
Precision-finished rotary heads with a brushed appearance for a high-quality machined look and consistent sealing performance
-
Built to exacting standards for dependable performance across a wide range of pump applications
Engineered to rigorous standards, SPS seals provide a durable, dependable alternative to common aftermarket or OEM options—compare them against your current line and see the difference.
Explore our full lineup of Single Spring Seals—PS replacements, pool/spa seals, and our SPS line.
Looking for more? Shop Pump Repair Kits, Parts & Accessories, and Gaskets.
-