ASI 502 is a one-part, moisture-curing RTV (room temperature vulcanizing) silicone that cures to a strong, silicone rubber that maintains long-term durability and flexibility. Fully cured, ASI 502 has excellent adhesion to glass, metal, porcelain, ceramic, wood, most plastics and many other nonporous substrates. A technician’s preferred silicone for filling holes at customer installations.