Abstract: The present invention is directed to providing a simple, cost effective device for tightening a restraining device such as a belt, strap, rope or the like that requires very little space, and that can be easily operated to provide complete tightening of the restraining device, even when the restraining device is in a difficult to reach area. Exemplary embodiments can be configured as a unitary structure wherein arms of the unitary structure are each slotted and attached to a base of the unitary structure so that a belt can be easily inserted into the slots. The unitary structure can then be used to clamp the restraining device, such as a seat belt used to hold a child safety seat, in place. Tightening of the belt can be achieved through the use of a removable lever that tightens the belt with each rotation. Upon tightening of the belt to a desired tension, a secure locking mechanism, such as a nut, can be used to hold the belt in its tightened state without concern of belt slippage.