Spacers are small pieces of material that sit between the screw head and surface to create or maintain a space clearance between two things. Spacers come in a range of different sizes and lengths (2 mm to 50 mm spacer), depending on the space required. Their body shape can be hexagonal or round and they are also compatible with different screws, such as M3 and M4, but they are not threaded.
Spacers come in different materials, including nylon, stainless steel, brass, ceramic, POM and aluminium. Metals often provide a more aesthetically pleasing finish for visible applications and nylon is ideal for the high corrosion resistance. The spacer hole is usually round to allow the bolt or screw to pass through.
Standoffs are like spacers in that they provide space and have a hex or round shaped body and two openings. The main difference is that standoffs are usually threaded onto the screw and the threads can be male or female.
A spacer can be used to position parts within an assembly, to lift sections making sure there is enough room for the heat to dissipate and to separate or to create a space clearance between two items. Spacers can be found in: