360° head has three scales calibrated to be used with International Standards of Measurements.. Suitable for health facility and at home use. 6-inch arm allows for measurement of joint limits and range of motion as well as check extension, flexion, abduction, adduction and rotation.. Displays linear scale measurements in inches and centimeters. 360° angle scale reads in 1° increments for more accurate readings.. Clear plastic material allows for easy observation when measuring the joints axes..