KN Crowder CT-51 Mortised Automatic Door Bottom – 3’0″ LongCT 51 x 3'0" Anodized aluminum and neoprene construction For mortised mounting inside the bottoms of wood doors minimum 1 3 8 thick Extruded aluminum housing measures 17 32 thick x 1 1 2 high; overall housing is 1 3 16 wide including flanges Adjustable plunger with maximum 5 8 drop Supplied pre drilled and furnished with mounting screws Can be shortened up to 6 on the field