In 1981, Schaller developed and got the patent for a totally new category of product, which revolutionized the connection between guitar and strap. With its unique design and functionality, Schaller has been setting the standard in strap locks for decades. In 2018, Schaller paves the way for the next generation of revolutionary strap locks. Schaller proudly presents: The new S-Locks, S for save, S for silent and S for Schaller strap locks. These new revolutionary S-Locks are silent. They feature one-piece hardened steel strap buttons, aesthetic design, perfect handling, an elegant Lock-Wheel and all former hiccups have been tackled. 3 pieces = 1 S-Lock - perfect. Strap button New and unique solid one-piece strap button in hardened steel with self-tapping wood thread. Simply screw it on with an Allen key (size 3 mm). New Lock-Wheel with unique 3-Step security function: 1. Screw the lock wheel with patented self-locking thread tool-free by hand, you already protect your guitar sufficiently (the round shaping must be facing the pull-up ball). 2. Use a 2 mm or 5/64'' Allen key or screwdriver to tighten it for maximum security. 3. Use the micro cone-top screw to attach it permanently. You will never lose your wheel again. Finally put all parts together and just listen carefully...Give it a shake, give it a roll and prepare to be amazed: It is silent. New silent feature for noiseless performance while moving and playing your instruments. All S-Locks come in a new and attractive reusable crystal box. Two more things ... 1. S-Locks are fully compatible with all existing Schaller Security Locks. 2. Only one strap and one pair of S-Locks, ...for all your guitars. Enjoy all the benefits of the new S-Locks using one single strap. Simply use the new strap buttons replacement kits to new S-Locks for all your instruments.