The Viper Bodyguard Professional has a special adjustable leather harness that is very high quality, chosen for it's suppleness and toughness. The leather rig is very low profile and yet adjustable in all aspects. This adjustability allows a perfect fit for all body types through self customization. The Bodyguard Pro can be built for vertical or horizontal carry and both have an extra mags carrier on the off side.
The Bodyguard Pro built for Vertical carry anchors the holster, and the offside magazine carrier, to the belt on both sides. Vertical orientation accommodates larger/longer firearms better, especially where the wearer has a smaller frame and wants to carry a larger firearm. The vertical orientation also provides a little more support and weight distribution for the heavier larger frame high capacity handguns since the leather rig acts somewhat like suspenders. This is a major advantage to those without a defined waist. Instead of having the weight of a handgun on the belt adding to already falling trousers, the vertical shoulder rig helps to keep the pants up and the stabilizes the handgun at the same time.
Horizontal orientation is not tethered to the belt and the determining factor here is that the handgun should be shorter than the depth of the wearer's chest from front to back. Horizontal rigs will not have the tie down to the belt so the advantage here is that it is easier to put on and take off. Also the horizontall rig does not require wearing a belt.