1 1/8 inch dia outer thread, 12 TPI. Center thru hole = 3/8" pipe thread, Material = ASA plastic that is oil resistant.   Perfectly smooth running threads.  O-ring gasket included.   This is for one part only.   3/8 inch pipe nipple is not included.  It is best to confirm your thread size by measuring the OD of the dip stick thread.
 
The maximum usable temperature for ASA (acrylonitrile styrene acrylate) is generally considered to be around 93°C (199°F), meaning it can withstand sustained temperatures up to this point without significant deformation or degradation in properties; making it a good choice for applications requiring moderate heat resistance.