4" long 1/2" MPT Thermowell with 1/2" FPT Inlet.  Thermowell measures 4" from the face of the MPT threads.  Has a 1/2" FPT threaded inlet to secure a dial thermometer or strain relief, etc.  Made of 304SS  ID of thermowell is .305".  This part threads into an existing 1/2" FPT coupler or fitting and is not designed to be weldless.