This weldless thermowell is made from solid 304 stainless. It has a straight ½” BSP thread which is 40mm Long. It includes a silicone o-ring, a stainless steel slimline nut and also the extra long nut for mounting directly to our 3 inch dial thermometers. This thermowell can also be used in conjunction with our digital temperature controllers. The probe will slide straight into the thermowell.