The ASTM #62 & #70F Precision Thermometers has a strict manufacturing tolerance. Accuracy is assured by inspection and testing of samples from each production run. The thermometer is supplied with a statement of compliance to E 1 and E 77 requirements. The ASTM Thermometer is yellow-backed glass with permanent graduations, mercury-filled. The set includes one each of ASTM 62 to 70F in a velvet-lined protective case.