A restraint system includes a first member including a first hole and fixable to a seat frame, a second member including a second hole and slidably coupled to the first member between a retracted position in which the first and second holes are aligned and an extended position in which the first and second holes are spaced from each other, a buckle housing fixed to the second member, and a tongue including a third hole and insertable into the buckle housing to an inserted position in which the second and third holes are aligned.