A clamp used to attach an accessory to a skateboard or longboard. The clamp, in its preferred embodiment, consists of a mounting plate, a clamp bottom, and a clamp top. The mounting plate is used to attach to the top deck of the skateboard or longboard using the existing truck hole mounting pattern. The clamp bottom will attach to the mounting plate and the clamp top will attach to the clamp bottom with an accessory secured between the clamp bottom and top. It is understood that the pieces of the clamp can be attached using various methods and construction methods can vary. The purpose of this clamp is to allow the rider of a skateboard or longboard ability to attach accessories to a board. With the attachment of an accessory, a rider has the flexibility to customize their board to meet their needs and create a hybrid modular board.