This is a DeSantis Gunhide Chest Holster known as the M40, model M40BA05Z0.
Handgun hunters were the first in civilian life to pick up on chest carry. Concealment wasn't an issue" and a big revolver was comfortable and accessible in this position. The hunter's chest holster reached its height of development with the recent Terminator(TM) design by Gene DeSantis. The Black Mamba(TM) carries even the 72 ounce S&W 500 with total comfort and security. Available in black molded nylon. Fully adjustable tension device.
Features:
Made from black molded nylon
Most models feature a fully adjustable tension device
Comfortable chest rig where concealment is not an issue