Beadex paper-faced metal trims reinforce architectural edges, protecting them from chipping and cracking, producing corners that stay beautiful despite the stresses of normal building movement and everyday wear-and-tear. Made with strong paper tape laminated to a sturdy, rust-resistant metal form, ensuring excellent adhesion of joint compounds, textures, and paints. B4 series is an "L" shaped profile. Designed to be used where wallboard abuts with suspended ceilings, beams, plaster, masonry and concrete walls, as well as untrimmed door and window jambs.