An amazing Kart that is for everyone, moms and dads included. Even grandma and grandpa will enjoy this Kart. For those who donÃ¢€â„¢t have the right balance or the right weight to enjoy the ride of a hoverboard or if you are a Go-Karting Enthusiast, you can now sit back and relax. ItÃ¢€â„¢s an add on to your Smart2 and Smart2HX Series Hoverboards. They are designed for all hoverboards from 6.5Ã¢€Â all the way to the biggest hoverboard out there, the 10Ã¢€Â. DonÃ¢€â„¢t forget your helmet when the race begins.