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Two small black rubber O-rings on a plain background

Watercool

Watercool Replacement O-Ring GPU-X² GPU-X³ Multi-Link 2-Pack WAT-0078

SKU CH-10Q2-R0WH5 MPN WAT-0078

Two replacement O-rings seal the connection blocks of HEATKILLER GPU-X² and GPU-X³ water blocks and their Multi-Link variants

  • Product colorBlack
  • Key featuresTwo replacement O-Rings for the connection blocks of the HEA
  • Ensures leak-free GPU block connections with two precision O-rings
  • Compatible with HEATKILLER GPU-X² and GPU-X³ terminal blocks
  • Fits Dual, Triple and Multi-Link configurations for versatile use
  • Black finish maintains a clean, professional loop aesthetic
  • Ready-to-install pair keeps a spare on hand for maintenance

Replacement O-Rings for GPU-X Water Blocks

This two-pack supplies black O-rings made for the connection terminals on HEATKILLER GPU-X² and GPU-X³ water blocks. They seal the junction between the block and Multi-Link fittings so coolant cannot escape. Each ring is a direct drop-in for the original seals. Swapping them out restores a leak-free loop without tools.

What the 2-pack changes for maintenance

Having two rings on hand lets you service both inlet and outlet ports at once or keep a spare for future disassembly. The black colour matches the standard finish on Watercool fittings so the repair stays visually consistent. No lubricant or adhesive is included; apply your preferred coolant-safe grease during installation.

Compatibility decides fit

These O-rings fit HEATKILLER GPU-X², GPU-X³, Dual-Link, Triple-Link and Multi-Link connection blocks. They will not seal other brands' terminals or older Watercool series that use a different groove profile. Verify your block model before ordering to avoid a mismatch.

How it compares

Measured against everything we stock in PC Cooling Fans, at today’s prices. Recalculated every night.

Price $1.25
Cheaper than about 99% of the 8,338 comparable items (median $19.99).

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Specifications

Product
Brand nameWatercool
Model nameWAT-0078
Part numberWAT-0078
Product colorBlack

Questions about this item

When should the O-rings on the HEATKILLER GPU-X² or GPU-X³ connection blocks be replaced?

Replace them whenever you disassemble the blocks or if you see any cracking, flattening or coolant seepage around the seals.

What is the first sign that an O-ring on a GPU-X² or GPU-X³ Multi-Link is failing under constant pressure?

A slow coolant leak at the joint between the connection block and the Multi-Link fitting.

Do the black replacement O-rings for the GPU-X² and GPU-X³ blocks add any measurable heat or noise to the loop?

No, they are passive seals with no moving parts and no electrical components, so they generate neither heat nor noise.

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