Cold Steel’s Double Agent I neck knife possesses a significant set of advantages worth noting. Designed by Zach Whitson, it is thin, flat, and super light (a little over 3 ounces including sheath). This makes it easy to conceal and very comfortable to wear. It’s most audacious and notable feature, is its double ring handle design. Slip an index finger through the front ring and your pinky finger through the rear ring and close your fist to obtain a forward grip and vice versa for a reverse grip.