BMax SN890CH34 Clipped Head 2-Inch to 3-12-Inch Framing Nailer ReviewbP PP Max SN890CH34 Clipped Head 2-Inch to 3-12-Inch Framing Nailer PAnti-double fire mechanism (US patent 5597106, UK Patent 2286790)PDial adjustable depth controlPEasy jam clearance door (Patent pending)PTangle free swivel plug (Added from 2002 production)PLock-out Mechanism - Tool will not fire unless more than three nails are in the magazineP