Precision Hydraulic Hand Dynamometer from B&L Engineering™. 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 based on 12 different weights at all five handle positions. Method of Dynamometer Calibration defined by Elaine Ewing Fess, MS, OTR, CHT, FAOTA. Officially CE Marked. Includes double-walled rigid plastic case with fitted foam to protect the instrument when not in use.