Riser pads come in a set of two and are 3mm (1/8inch) thick. They are placed between your trucks and the board while mounting and help with absorption of impact. They also increase the height which gives lesser wheel bite. If you are ollie-ing a lot and up breaking boards, buying a pair of these will help make your deck last longer as they will prevent pressure cracks from developing. It is suggested to use 1.25 inch hardware if you are using riser pads so that they fit comfortably.