The linear scale has inches and centimeters. The stainless steel finger and small joint goniometer measures the range of motion of finger joints (metacarpo-phalangeal and interphalangeal) and other small joints including toes. The head has two opposing 180 scales which are marked in 5 increments. The easy to use goniometer allows the therapist to use only one hand to measure 110 flexion and 40 hyperextension.