Nord-Lock Washer M18 (19.5mm x 29mm) in 316L Stainless (NL18*SS), per pair

Nord-Lock washers, also known as wedge-locking washers, secure bolts with tension instead of friction. Working as a pair, these washers create a wedge-effect underneath the bolt head or nut so that the joint is prevented from loosening unintentionally. Nord-Lock washers are quick and easy to install and remove, and they are reusable. Supplied as a glued pair, they are appropriate for use in vehicles, for DIY and for watersport equipment. Most sizes are available in two external diameters: the smaller standard type listed here, and the larger SP type.