12Pcs Strap Locks Guitar, Metal Guitar Strap Locks and Buttons, Metal Heavy Duty Guitar Straplocks Replacement Button Security Straplock for Classical Acoustic Electric Guitar Bass

I need strap ends more than the lock part. You will get a batch now and then that are out of spec or not assembled right. The ball knob is press fitted to the retainer. On a rare occasion the knob can pull off. They can be repaired by clamping a flat end punch in a vise and tap the ball back on. Careful not too much! If you do the retainer won't extend far enough to retain the end on the guitar. Even the "Name brand" can have this problem.

Guitar teachers- bought has an Xmas gift for students. Thought it was great to finally find strap locks at an affordable price. Several came broken, a few were stuck together and very hard to remove, and overall the quality is suspect. I haven't used them but I would not want to put them on for a show. Also did not come with directions, which is fine if you know how they work. Overall, I would buy more expensive ones.