These Golden Ball Tracer BBs offer unparalled performance in the field. When fired with an airsoft rifle or pistol equipped with a tracer unit, these 6mm rounds glow in the dark! Goldenball BBs are engineeed with a diameter of 5.95 mm with a +/- 0.1mm variance for a perfect fit with tightbore inner barrels. This package contains 2000 rounds of 0.20g BBs.