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. Cannot be painted. 12 per bag.