Bulb Weatherstripping Seal—Bulb seals conform to doors, compensating for irregular surfaces. They restrict airflow better than flat seals. Made of silicone, they withstand high temperatures and UV rays.

Flat Weatherstripping Seal—Flat seals are made of a graphite/rubber blend, which expands by as much as 10 times their original thickness in extreme heat to completely seal out flames. Also known as intumescent seals, they’re commonly used in fire doors, which often have a built-in groove shaped to fit them.

Finned Weatherstripping Seal—Finned seals have two flat fins that create multiple sealing points against a door. They compensate for uneven surfaces better, insulate better, and last longer than flat seals. Made of TPE, they resist UV rays like silicone bulb seals and withstand abrasion, tears, and solvents better. However, TPE will deteriorate and crack at temperatures above 250° F.

V-Strip Weatherstripping Seal—V-strip seals are made of stiff, folded material. One arm mounts to your door frame while the other presses firmly against the door to block airflow. They’re also known as tension seals. Bronze seals are durable and corrosion resistant, and often used on historical buildings to match the existing design. Stainless steel seals are stronger than rubber ones and more corrosion resistant than bronze ones. Often used in marine environments and food plants, they won’t degrade from contact with mild chemicals or detergents.

UL 1784—Seals that meet UL 1784 are rated for use as smoke and draft control gaskets.