PRO GUN Modified Acrylic Sealant is a quality general purpose modified acrylic caulk. Designed for sealing gaps filling cracks, setting windows, trim, doors, sinks, counters and a variety of substrates. Once cured, it can be painted and will form an airtight, water resistant seal that is mildew resistant. With 45 year durability, it exceeds ASTM C-834.