Single Spring Mechanical Seal SPS-501 | PS-501 Equivalent

SPS-501 single spring mechanical seal, equivalent to industry standard PS-501 / 501. Fits 5/8″ shaft with 1.25″ x 0.406″ seat and Type A/6.

Typical applications: Centrifugal pumps, mixers, and other rotating equipment.

Key specs: Shaft size: 5/8″ single spring seal • Seat: 1.25″ x 0.406″ • Rotary OD: 1.218″ • Working length: 0.811″

Design & construction:
Rotary head Type A/6. Electro-polished 304 stainless steel metal parts. Elastomeric bellows. Non-directional (independent of shaft rotation).

Material: CAR/CER/NIT — Carbon vs. Ceramic faces, Nitrile 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.

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