Successfully teach the concept of the rotating force, or torque, with this unique device. First, place the hanging mass close to the gripping handle. Students will find it easy to hold the rod horizontal. Then, slide the same mass to the end of the rod-not even your strongest student will be able to grip tightly enough to prevent the handle from twisting in their hands! Effectively demonstrates how lever-arm distance influences the strength of a torque. Comes complete with instructions and 1-kg hooked mass.