2238-14-3 Cooper 2" Dial 8" Stem Thermometer With Clip Glass Lens NSF 50/550 °F/°C: The 2238 series has a tempered glass lens and features a stainless steel vessel clip. Model 2238-14 is perfect for monitoring dough through the yeast-kill process and features a higher range then the 2338-06 of 50° to 500°F/°C.