The new S-Locks. S for save, S for silent and S for Schaller strap locks!
099-0690-000 Fender/Schaller Chrome Strap Locks and Strap Buttons Set
Schaller Strap Buttons for S-Locks - StewMac
Schaller 445 Nickel Finish Strap Lock Set – Twin Town Guitars
Amazon.com: Musiclily Flat Head Guitar Big Strap Locks System Schaller-Style Straplocks Parts for Electric Acoustic Guitar Bass,Gold(Pack of 2) : Musical Instruments
Schaller Strap Lock - Gold or Nickel - Greg Boyd's House of Fine Instruments
Amazon.com: Schaller S Locks Guitar Strap Locks and Buttons (Pair) Gold : Musical Instruments
Amazon.com: Musiclily Guitar Bass Schaller-Style Security Straplocks Round Head Lock Strap Pins and buttons Straplocks System for Fender Electric Guitar Bass Replacement,Gold (Pack of 2) : Musical Instruments