The New Sterling Grizz DP Trap. With heavy duty chain and swivel attached. MADE IN THE USA! Features super strong Music Wire Springs....The strongest spring in the DP industry. New "Mud Ejections Window" for the restraint bar. New longer TwistLoc Anchor System for soft ground conditions. Larger drain hole that can be utilized for the optional TwistLoc 360 swivel anchor. Sterling ST500 swivels with #2 machine chain.