This tool is designed to measure both active and passive motion of the MP hand joints and interphalangeal joints, and it can be positioned on the volar surface of the fingers to assess hyperextension or placed laterally along the joint’s long axis.
It measures ranges from 0° to 180° in 1° increments, folds to a compact size of 10 × 5.4 cm when closed, and is constructed from thick, durable plastic.