Grundfos 12mm Mechanical Seal — OEM 00985769 / 985204 / 00435045

Direct-fit Grundfos 12mm mechanical seal replacement (shaft seal) for Grundfos MTH and CR-series pumps. This seal uses a durable three-prong tungsten carbide rotary face and is commonly ordered by OEM part number to ensure fast, accurate matching. Cross-references include 00985769 (confirmed), plus 985204 and 00435045 (customer-supplied alternates).

Seal Details

• Shaft size: 12mm

• Rotary face: Three-prong tungsten carbide

• Applications: Grundfos MTH 8-5015, MTH/C 2/4 series, CR & CRK pump models

• OEM reference numbers: 00985769, 985204, 00435045

Tested model compatibility (based on customer use)

• CR4-120 U-G-A-AUUE — Model: C 41006072 xx 9809

• CRN4-50-120 (confirmed same seal)

• CRK2-150/15 A-M-A-AUUV — Model: C, 3KW

Fitment note: Grundfos seals are often identified by part number + shaft size—always confirm your 12mm shaft and match your existing seal style before ordering.

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