What is Snap fastener?

A snap fastener is a pair of interlocking discs, made out of a metal or plastic, commonly used in place of traditional buttons to fasten clothing and for similar purposes. A circular lip under one disc fits into a groove on the top of the other, holding them fast until a certain amount of force is applied. Different types of snaps can be attached to fabric or leather by riveting with a punch and die set specific to the type of rivet snaps used , sewing, or plying with special snap pliers.

Snap fasteners are a noted detail in American Western wear and are also often chosen for children's clothing, as they are relatively easy for children to use compared with traditional buttons.