Measures grip strength from 0-200 lbs/0-90.91 kgms at five handle positions. Calibration certificate included with correlation coefficient of .9994 or higher and mean deviation less than 1.5 lbs base don 12 different weights at all give handle positions. Method of Dynamometer Calibration defined by Elaine Ewing Fess, MS, OTR, CHT, FAOTA. Officially CE Marked. Two-year warranty. Includes double-walled rigid plastic case with fitted foam to protect the instrument when not in use.