The design is nice, but the tracks fro the metak joints are super flimsy. It came out of the track the first time opening. My son, 11, used it twice and the metal finally became so fatigued it broke.This this is cheap and worthless.DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!DO NOT BUY!