Schaller S-Locks M CH

I have the old design Schaller locks on most of my guitars. Excellent quality. This new design has 3 "improvements" - 2 of them are great, 1 isn't. The old hexagonal nut and washer were a real pain - always coming undone and difficult to tighten. Schaller have solved this with the new design. The new locking ring is easy to tighten, needs no washer and using an allen key through the two holes in it you can really tighten it and you can lock it in place using a small screwdriver on the locking screw. Great design, big improvement.
Now the not so good news. The new "silent" locks require very very precise machining or they can be too tight on the button causing the button to unscrew as the strap moves or to not clip in properly. I bought 2 sets - by mixing and matching I got 1 set to work properly. Thomann replaced the poor quality ones in record time. Well done Thomann.
Comment for Schaller product development team. Do you really think that a guitarist playing in front of his Marshall cares about his strap locks rattling ?? I don't - I can't hear it !!!!! I want them to lock properly and rotate freely. Unless your are machining to the exact micron tolerance your new design is too tight

I have been a long-time user of the old Schaller security locks and have always been happy with their use, so I bought a set of the S-locks to go on a new guitar. I didn't realise they had upgraded their locking system, and it fixes the one issue I have with my old locks. Will be ordering additional pairs for my old guitars.

The main feature of the new locks is the ring that secures the strap in place. The old strap locks only used a washer, which could sometimes loosen gradually. The new ring is easy to tighten, plus an extra screw ensures that it remains securely in place. Can highly recommend.

One small downside is that the bolt of the S-locks is taller so it sticks out more. Not a deal breaker, but slightly less comfortable for some guitars with the strap button at the back (e.g. SGs).

Also, for those who still have the old Schaller security locks, as far as I can tell the new "strap hooks" also seem to work well with their old locking system.

These are the absolute pinnacle of Strap Locks in the world today. They are also the most expensive. They are very well machined, with a great design.

They've 'cured' the rattling sound that their predecessors made when you shook the strap. They sit rock-tight on the strap button.

The Strap-lock itself has a longer shaft allowing it to be used with very thick straps without having to cut/trim the strap material to make the top lock it fit, which the old ones suffered from.

Two issues though: -
1) The strap button has a combined wood tapping screw - not like any stock screw used by anyone else. It'll tap a new screw-thread in your guitar body. Be careful, as it'll often not go in totally straight, and end up being slightly misaligned when it's screwed in. I've had this a few times using these. Maybe pre-drill a pilot hole?

2) The button/knob, to release the strap-lock off the guitar, is harder to use than the old ones, which had a bigger 'handle'. These are more finicky to release.

The finish is perfect, and they're available in more finish options than any other strap-lock currently available. All in all, well recommended.