Dunlop Strap Locks Dual Design Nickel (SLS1031) Set (2 units for instrument and strap) adapts to instrument by replacing existing strap pins/screws with special Straplok® System buttons/screws. Two strap attachments are included for your strap. The Original version provides a slim button design. The Dual Design model has a wider flange button, which provides extra security. Dunlop Accessories Tools and tricks of the trade! From the garage to the arena-players, luthiers, and techs prefer Dunlop accessories. Live to Play Live® ...