The switch mounting boxes, or enclosures are often recessed within a finished wall. The knife edge is recessed in a groove in each flange. The headlamps have square and slightly recessed bezels. Two small window casements are deeply recessed and have marble window ledges. The floor was a corrugated sheetmetal insert, secured with 26 recessed bolts. Credited to Katkhuda the gate has two doors, each surrounded by recessed arches. It has deeply recessed windows on each face and is finished with a moulded cornice. Plugs are shaped to prevent finger contact with live parts, and sockets may be recessed. Some items were specially designed for quilling with recessed surfaces. The corresponding socket is recessed to prevent shocks. Then the U-shape watertight seal is recessed back closer to the upper aqueduct door. A design of recessed niches decorates the lower edge. Its door is recessed and slides to open. Such a flat-headed screw may have a slotted, cross, square recessed, or combination head. The roof flaps deploy because they are recessed into a pocket in the roof.