Specifications Platinum RTD Sensors: ± 0.1% @ 0 C, Alpha: 385 per DIN 43760 Nickel RTD Sensors: (#2) ± 0.5 C @ 0 C, 5000 PPM/K T.C.R. Nickel RTD Sensors: (#4) ± 0.5 F @ 70 F/21.1 , 6000 PPM/K T.C.R. Balco RTD Sensors: ± 0.5 F @ 70 F/21.1 C, 4300 PPM/K T.C.R. Thermistor Sensors: ± 0.2 C interchangeability @ 77 F/25 C Probe Material: 1/4" / 6.3mm O.D, 0.020" / 0.5mm wall 304 Stainless Steel Flange Material: Galvanized Steel Bulkhead Fitting: Brass with poly compression sleeve Plastic Enclosure: Polycarbonate 30% glass filled, rated UL 94V-5-0 Steel NEMA-1/IP-30: 18 Ga. Galvanized Steel Steel NEMA-4/IP-65: 18 Ga. Cold Rolled Steel, Baked on Enamel Operating Temp: -40F/-40C to 210F/100C Ambient Temp: -40F/-40C to 160F/70C Warranty: Five Years (Lifetime on Moisture Migration) U.S. PATENT NO. 6457857, 6555748, 7036224