1A-Cooling Blacklord 240 Watercooling Kit
 

The base of the fittings includes a neoprene "O" ring to make it watertight. Tubing is attached by unscrewing the knurled ring, slipping it over the tube and tightening. To avoid the tubing from twisting as it's tightened, moisten the tubing with a little water - it's just enough lubricant to avoid twisting.

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