1Double Side Design: This massage hammer has double sided design, with a flat surface for scraping and a convex surface for knocking and massage, built in elastic column to ensure safe operation. 2Stretchable Handle: This handheld massage tool has a retractable handle with a range of 2441.5cm, which can be adjusted by pulling out the buckle and tapping any part of the body. 3Multiple Purpose: This manual knock massager can penetrate deep into the tense fascia of the body, massage painful knots, help you effectively relieve stress and tension. 4Applicable Areas: This massage tool is suitable for the back, neck, legs, shoulders, thighs, etc., soothing meridians, relaxing the body and mind, releasing pressure, and promoting circulation. 5Comfortable Grip: This stretchable knock massager is comfortable to hold, easy to operate and labor saving, making it very suitable for use at home, in the office, or during travel.