Fine tune your car's Center of Gravity (CoG) and optimize performance and stability. Includes four 1/2 oz (14.1 g) screw-in Tungsten CoG Weights™. Use weights individually or as 2 to 4-unit sets. Screw-in and adjust with an Allen wrench. Weights are 3/4 in length, tip to tip and 3/8 in Dia. Use a 23/64 in size drill bit when drilling a hole for weights in the car body.