This is a labor-saving hammer. It has several interchangeable hammer heads and can be replaced by opening four screws. The handle of the hammer is made of nylon material. The handle of the hammer is hollow. There is an elastic counterweight in it. When the hammer swings, the counterweight will slide to the front end to increase the impact force. When the hammer is lifted, the counterweight block will be pulled back by the spring, which can adjust the center of gravity and save labor.There are a variety of eye-catching color matching.