The improvement of the new generation jumper is as follows: 1) add axletree & bearing Base on the first generation adult model adds axletree between the top of the jumper and the spring so that it is more smoothly and natural for the activity. On reducing the resistance, making the product can jump higher and farther and more durable. 2) change the plastic strip for nylon strip New nylon strip has the design of a picture with running people on it which let people has fashion and popular feeling...And it is more firm and the button is more durable not easy to loose. User will feel more comfortable when the nylon strip tie to the legs. It is more practical use. 3) the root rubber can be taken off when it is attrite, It is more easy to change the root rubber It is very convenient to change the rubber in the bottom. User can easily change the rubber with much cheaper cost. And the second rubber will be more durable. 4) the plastic footplate is changed for aluminum alloy footplate The fixed plastic footplate of the first generational model has been changed for Adjust moveable aluminum alloy footplate. If you want the footplate move just take off the Axletree. If you do not want footplate move just fix Axletree on the Skyrunner. This humanism design not only reducing 400gram weight of the model but also can let the player feel more freely to jump and run, If Footplate With Moveable, It is good for walk, run. If fix up footplate, It will good for Jumper. You will find the feeling after you use! N. W: 7.0 KG G. W: 9.0 KG Meas: 88X29X38.5CM (Color Box) If order quantity less than container quantity, we will pack 4pairs/color in 1 big carton, In order to protect the Skryunner! Load Quantity/Container: 300Pairs/20Ft Container 600Pairs/40Ft Container 700Pairs/40Hq Container Load Limited: (Weight: 110~150 Ibs/50~70kg) (Weight: 155~200 Ibs/70~90kg)