G4 sealer is a clear, moisture-curing liquid sealer designed to waterproof and protect a variety of surfaces, including wood, concrete, brick, and metal. It is commonly used in construction, marine, and automotive applications. The G4 sealer is a two-part system consisting of a resin and a hardener. When mixed together, the two parts react to form a hard, durable, and waterproof seal that protects surfaces from moisture, UV rays, and other environmental factors. The sealer is easy to apply with a brush, roller, or spray gun, and dries to a clear finish that does not affect the appearance of the surface it is applied to. It can be used on both horizontal and vertical surfaces, and is resistant to abrasion and chemicals. G4 sealer is commonly used in marine applications to seal and protect boats, yachts, and other watercraft from the effects of saltwater, UV rays, and other environmental factors. It is also used in construction to seal and protect concrete, brick, and other surfaces from water damage and corrosion.