What Toor Knives says:
The Horizontal Carry Belt Loops were designed to offer the user a practical lightweight horizontal mounting option and although it is meant for belts, we have seen it used on many types of gear. The straps themselves are made from a heavy-duty rubber with attached directional fasteners, which are locking button-style mechanisms trusted by the US Military for airborne operations.

Please be aware the Horizontal Carry Belt Loops do not fit Toor's Leather Sheaths like the Field 1.0, Field 2.0 and Field 3.0.

Instructions:

1. To lock and release this directional fastener, first locate the locking tab on the female side of the button (it is a small deviation in the ring of the button).
2. When attaching the female side to the male side, make sure the opposing die of the locking tab is set in, then simply press down the rest of the button.
3. To release the mechanism, pull back the front of the button (closest to the edge of the strap) and it will easily release.

Quinn Knives' take: 
For that true horizontal carry look, the horizontal belt loops are tough to beat!