Alfano H20 Fitting
This fitting is used to assist in engine water temperature reading. Splice into your radiator hose and screw the Water Temperature Sensor straight in. On many of the new TAG motors this is not necessary because the head already has a fitting, but most shifter karts will require this fitting.
It is available in 2 sizes (17mm or 19mm) but the majority of karts are built using 17mm. If you are unsure measure your radiator hose to order the correct size.