Description Reviews USED Temperature Gauge Adapter. This piece replaces a coupling in the coolant hose of any MINI engine or cut a hose on any engine and just add this coupler with some clamps. This coupling has a 1/2 NPT threaded tap for the sender or adpater and has (2) 1 1/4 inch ends that are 1 inch deep. Now you can hook up an actual temp gauge to your car!