This type of 3-bar "slider plate" is used when mounting a restraint harness using the wrap-around method. It can also used to install a bolt-in or snap-in end plate (sold separately) on a wrap-around belt. Many driver restraint harnesses include a slider like this to hold the factory mounting plate to the belt.
The 3" wide slots in this steel adjuster are for use with 3" straps only. It can be used on most lap belts and standard 3" wide shoulder harnesses. Sold individually.
Installation is easy:
1. Thread your harness strap through the slider plate by passing it under the first bar, then over the middle bar, then under the third bar.
2. Wrap the free end of the strap around your rollbar or chassis tube (or through the slot in your mounting plate) from the bottom to the top so that the free end ends up on top of the rest of the strap.
3. Pass the free end of the harness strap back through the slider plate going under the third bar, over the middle bar, and under the first bar.
4. Adjust the length of the strap as needed, taking care to position this plate as close to the mount (rollbar or mounting plate) as possible.
5. Pass the free end of the strap back over the first and middle bars of the slider plate, and under the third bar. This critical step locks the adjustment in place.