bought in a promotion of joola. It came with a net and a box of balls. It was the best thing I did, I can train like no opponent can, especially topspin against defensive players. The Underspin that the robot can achieve is superior to any human being. The materials used are plastic, but I really appreciate it. it is a very light robot and fits anywhere. It looks fragile but in reality it is a battle tank. It stays in the trunk of my car and it has never broken down, believe me it jumps a lot in the trunk hahahahaha. It's just right to shoot the balls and no deviations. In addition to training, you can compare material from table tennis, blades and rubbers. The capacity of balls a can be changed if we stick a plastic around the part that is up 
When placing the balls we have to be careful not to enter directly into the place where the balls are thrown, it can get stuck, just turn the wheel a little bit which controls the entry of the balls. Nothing a person doesn't get used to. I recommend this robot to anyone who wants to spend a little money. I'm not going to mention that it oscillates, that it has a remote control, etc. because that's in the product description!
When placing the balls we have to be careful not to enter directly into the place where the balls are thrown, it can get stuck, just turn the wheel a little bit which controls the entry of the balls. Nothing a person doesn't get used to. I recommend this robot to anyone who wants to spend a little money. I'm not going to mention that it oscillates, that it has a remote control, etc. because that's in the product description!