D’Addario Auto Lock Guitar Strap, Black, D’Addario Item 50BAL00.
Simply slide the strap end over the guitar strap buttons and you are locked in. The grey latch is spring-loaded so it automatically clamps down on the strap button and will not release until you want it to. Just push up on the grey latch, slide off the end, and the strap is removed.
• Simple, integrated strap lock design
• Soft nylon material adjustable from 30″ to 55″
• Works with most strap buttons
• Ned Steinberger design