Work your entire core, legs, shoulders arms and develop explosiveness with the MDB Slam ball. This durable, sand-filled dead weight ball is gym-tested and will hold up slam after slam! The pliable, rubber like surface provides the ultimate grip. For use with wall, floor and rebounder slams. Specifications Available in 10,15,20,25,30,35,40lbs increments Ringed shell designed for optimal grip Made for tossing, throwing and slamming Made from rubber like, PVC