One of the most underrated ar rails on the market, hand's down! - Troy SOCC 5.56mm Low Profile BattleRail

I have been using these rails for almost 15 years starting with some of their very first models. They are slim, lightweight, solid and very easy to install. This newer version with M-Lok compatibility could be one of the best rails on the market. Mounting system locks right up to standard GI Barrel nut so no special tools, shims or timing required. These rails also integrate seamlessly with the upper with no locking or tension tabs below the rear of the handrail which can eat into your hands. Once you use one of these you probably won't ever use another rail again.