Am'D Screw-LockDescription Am'D Screw Lock is a high quality D shaped carabiner designed by Petzl for bouldering and climbing applications. Am'D is forged and heat treated from durable aluminum anodized matte black with an H cross section for a firm grip and reinforced construction. Screw Lock systems make it ideal for foul weather where mud and dirt might impede the work of the automatic lock. It allows an excellent load of necessary devices used in climbing, such