XT Wheelz Off-Road skateboard wheels are the "original" and very first off-road skateboard wheels used for mountainboarding or also known as "dirtboarding". These wheels come in a set of four. They are 112mm in height by 65mm wide. They are solid patented Goodyear rubber made in the USA. You won't find wheels like this anywhere else. These off-road wheels are super durable and tough and ready for rugged conditions. Or if you want you can also ride them on the street, as they have a 13mm wide flat ridge in the middle. This ridge allows you to cruise on them like any other standard skateboard wheels. Use these wheels on a regular skateboard deck, although we do recommend something wider. Or you can ride with them on a longboard. We recommend using wide trucks and you are required at least 1" of riser pads for safe clearance to prevent wheel bite. Four 1/2" hard risers from Khiro are perfect. Use any standard size skateboard bearings for them and our recommendation is something all-weather as they will take some serious punishment.