1.
Remove the band from your guitar or bass and set it aside. Use the screwdriver to unscrew each of the two strap pins where your strap is attached to the instrument. Under these pins are usually small circular pieces of felt that act as cushions; keep them.
2.
Set the pins aside. If desired, insert one to three toothpicks into each of the pin holes on the instrument body. This is a common method of creating a tighter fit to hold the strap in place. Break the ends of some toothpicks protruding from the holes.
3.
Replace the felt pieces over the pin holes and insert the screw part of the belt ratchets into the holes. Screw them on completely. After each band lock pin has been secured, replace the guitar or bass band. Attach the strap latch heads over the pin heads, either by screwing them on or by sliding the head over the pin.
Guitar and bass players usually try to prepare for unexpected problems that may arise during a rehearsal or concert, such as keeping extra strings around or a backup instrument on hand. Belt locking is another proactive approach; The dirty little hardware attaches the strap to the instrument, so that it will not fall off the player’s body and prevent any damage.
Source:danspela.com