E Support&trade; Multi Color Soft Crystal Water Paintball Gun Bullet Air Water Gun Toys Airsoft Plant Soil Non-fade, Non-Toxic, 100% Biodegradable, Non-Flammable A great learning tool, kids are busy for hours, having fun experimenting Crystal paintballs are easy to made Product size: about 11-13mm of the diameter after soaked water Color: multi-colors (send at random)