Coolant PipeSize - PlasticThreading Diameter (in BSP): 1/4" 3/8" 1/2" 3/4" Length (in inches): 6" 12" 18" Size - MetalThreading Diameter (in BSP): 3/8" (Standard) Length (in inches): 12" 18" Type - Plastic Regular Regular with Cock Flat Nose Y-Type