The Builders Edge Surface Block for Triple 3" for installing fixtures after the siding has been applied to the home, for use on Triple 3 in. siding . Mounting blocks are durable, maintenance-free, U. V. stabilized and constructed with color molded-through so they won't scratch, flake, or fade. Our patented Snap-On Trim Ring makes installation easy. Available in 24 colors to match your siding manufacturer and a Paintable option to easily match your home. Limited lifetime . Proudly made in the USA! .