A catch or latch is a type of mechanical fastener that joins two or more objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the other mounting surface. Catches range in complexity from flexible onepiece flat springs of metal or plastic, to multipoint cammed catches. A spacer is a solid material used to separate two parts in an assembly. Spacers can vary in size from microns to centimeters. They can be made of metal, plastic, glass and other materials. Shapes include flat sheet, cylindrical and spherical. Specifications. Height 0.05 in.. Width 4.1 in.. Length 0.65 in.