These are the End Of The Road Super Quick Fist Clamps. These are designed to hold objects ranging from 2.5” to 9.5” (64 to 240mm) in diameter. 2 clamps can support up to 100lbs (45 Kilos), and mounts with 3 #10 bolts or screws.
This is 1 clamp per package, and make for a safe and convenient means of securing equipment in your garage, or in your vehicle.