Clamp-On Surface Temperature Probe 3/16" to 1.25" Jaw Opening For TM150, TM250, TM350, TM360 & SH450 Series. All probes have 15ft / 4.5m leads. Probe Type, Surface. Common Uses, Surface temperatures of copper piping from 3/16" (5mm) to 1 1/8" (29mm), Response Time of 12 seconds and a range of -40˚F to 221˚F /-40C TO +105˚C.