Jumping Base really isn't that good. If you know how to build it it is okay, but the screws on the bottom are hard to put on, and if you flip the little plastic part over the bottom you can put the screws in but have no room to put the spring. Even if you cant put the spring on it's a pretty good blade. My friends and I were playing Beyblades at school and Jumping Base (without the spring on) smashed my other friend's combination Beyblade and hit it so hard that it hit my ither friend's stomach. If you can't figure how to get it together if you get it and you want the spring on, either deal with it or take it back. I hope this review was helpful and remember: LET IT RIP!