Nike SPARQ Speed Discs can be used by athletes and coaches alike to mark drills on any playing surface. Just sprint, touch and go. The separate indoor/outdoor color coded sets and low profile design make these discs easy to spot, but keep them out of the way during use. Green outdoor discs provide high contrast against turf, track or grass. Black indoor discs provide high contrast against light colored court surfaces for indoor training. One disc weighs: 1.8 oz. (50 gram). Sold in packs of 12.