CRL Gunther Ultra/Bond® and Extra/Build® Mirror Mastics are high quality adhesives formulated to provide a strong, permanent bond between electro-copper-plated glass mirror and various substrates. Both have been field tested for compatibility with silver, copper, and mirror backing. Both have an easy working consistency year round, and will adhere to a wide variety of substrates including drywall, wood, metal, glass, marble, and tile.

NOTE: Not for use on acrylic mirror. Use Cat. No. GN8 Gunther Prime-N-Seal Primer on all porous substrates. Application guidelines are available online for all Gunther products. Mechanical support systems are recommended for all mirror applications.

Gunther Extra/Build®’s viscosity provides for a build out of 2-1/2" (64 mm) without sag for custom mirrored walls or vanities, where construction is such that there are gaps of over 3/4" (19 mm) between the mirror and the substrate. At 72°F (22°C) it achieves approximately 20% strength in 48 hours, full cure up to 300 psi in 30 days. It comes in 10.1 Fl. Oz. cartridges and one gallon cans.