Thank you Sir. The ACG Harlot had the Schallers installed since it was built in 2009, I bought the S-Locks because they are compatible with the older Schaller strap buttons that came on the bass, they snap in crisply and are are really firm. When the Schallers are engaged it feels like both components become one solid unit, the Dunlops (which, btw, are on a much newer bass) rattle a bit and don’t inspire quite as much confidence.