Bolt on Bed Rails for Twin XL, Full XL, and Queen Size Beds These bed rails are Bolt-On and feature Headboard and Footboard brackets. These rails are quality made with pride in the USA. The side rails measure 2" x 1-1/2" (vertically) x 83" long. The Bolt-On Headboard and Footboard Brackets feature 2-1/2" or 4" centers on the mounting slots. Versatile: Twin XL, Full XL, and Queen in Size