Dr. Franks Calf PullerDr. Frank's Calf Puller The "Original" Calf Puller Features an adjustable heavy duty nylon strap, nickel plated chain and a quick release mechanism for easy, one person operation. Uniform tension helps prevent slipping or backing up of the jack. Utilizes a non slip 6 cam traction system to provide the counter thrust needed in the birthing process. Smooth cast steel rods are durable, clean easily and unscrew for easy storage. Jack body is cast steel.