GKTech - RADIATOR HOSE 1/8-27 NPT COOLANT TEMP ADAPTERWhen installing an aftermarket coolant temp gauge or setting up a header bleeder tank you'll need to tap into the return on your radiator hose. Fortunately for us, Nissan kept the inside diameter of all of the important Nissans the same size (confirmed list below). Simply cut a slit in your hose and insert this beautifully CNC machined aluminium piece. CNC machined aluminium and anodized black To suit 1 8 27 NPT temperature gauges (most common size)