The dimensions of the unit are the same as the real claymore, which is quite compact - 8 1/2" L x 2" W x 3 3/4" H. This reusable BB mine will use BBs of any size and weight. They can even be "recycled" BBs. We like cheap .12g BBs because they really fly. The charge can be up to 200+ BBs, but 25 to 50 BBs provide good coverage. Spring powered, it uses no explosives, no gas or electricity and can be used over and over again, even in the same game. Nothing else needed! It weighs only 2 lbs and is the exact size as the real Claymore. It will cover a 30 to 45 degree arc and projects .2g BBs over 40 feet.