Bondo fiberglass mat consists of interlocking strands of fiberglass to repair holes and gaps in jobs of any size from large to small. Use fiberglass mat on anything from automobiles and boats to tubs, showers, sinks, pools, hot tubs and more. Versatile repair material works on most any surface, including metal, fiberglass and wood. Slightly thicker than fiberglass cloth, Bondo fiberglass mat is recommended when additional strength is required on more severe repairs like larger holes and cracks. When used with Bondo fiberglass resin PN 401, 402, 404 (sold separately), repairs are 100% waterproof, making the products ideal for automobile, tub, shower, sink, pool, hot tub, boat repair and more. This product can also be used on additional surfaces such as wood, concrete and metal to provide extremely strong, durable and waterproof repairs. When properly used with Bondo fiberglass resin, Bondo fiberglass mat reinforces repair areas and allows for repainting so that the repair looks like the original surface once the job is complete. Fiberglass mat is easy to cut to size and shape for customized repairs on automobiles. Fiberglass mat is often used with fiberglass cloth and fiberglass resin for repairs. Once the patched area has cured, it can be sanded smoothly so that it is level with the surrounding surface. A fiberglass repair completed with resin and mat is fully compatible with being painted. Fiberglass mat consists of short strands of fiberglass bonded together with a resin. Fiberglass mat offers numerous other benefits, including a resistance to expansion or contraction as temperatures change. Fiberglass mat will not absorb moisture and is non-flammable. Our fiberglass mat is also resistant to most chemicals. Our fiberglass mat is highly pliable, enabling it to conform to curved surfaces on automobiles. The flexible nature of them at allows for customized automotive bodywork repairs on fenders, doors, hoods and other sections of the car body.