Perforations in the embedded leg allow concrete to flow around it, securing it in the wall. The exposed flanges provide a structural surface to attach the ICFLC-W and a wood or steel attachment. Installation is easy: Simply snap chalk lines, top and bottom, for the proposed ledge, mark the locations for the brackets, and cut vertical kerfs in the ICFLC. Builders have the option of either gluing the ICFLC to the block or placing a strap across it to hold it in place during the pour. www.greenblock.info