Builders Edge Shutter Lok patented fastening system makes installation fast and easy. Shutter Lok holds in any material: Vinyl, stucco, brick, fiber cement. Shutter Lok features a durable copolymer construction with molded through color so that there is no paint to ever scratch, flake, or fade. Installation requires drill with 1/4" masonry bit. 12 per bag. Made in U.S.A.