We sell 3 types of bronze weatherstripping. The first two are spring bronze, as they are flexible. The third type is interlocking, which is more rigid and not springy.
The first type of spring bronze weatherstrip is called "Pro Type" and is a single leaf of bronze. This weatherstrip is able to be rolled and thus is easier to transport in long lengths. There is a crease in this weatherstrip about 3/16" of an inch from one edge. The nails are nailed in along this edge and the crease causes the other edge to spring up away from the surface. This type of weatherstrip is suitable for filling gaps from 1/16" up to 1/4".
The second type of spring bronze weatherstrip that we sell is call "V Shaped" or "Cushion Type". This weatherstrip is suitable for filling gaps from 1/8" up to 5/16". Since it is folded, it cannot be rolled and must be shipped in long cartons or tubes. Shorter lengths are more economical to ship while 7 and even 8 foot lengths can be shipped by oversize parcel services. Pieces longer than 8 feet must be shipped by motor freight.
The third type of bronze weatherstrip that we sell is called "Interlocking" weatherstrip. This weatherstrip is not springy and the seal is achieved either by two different metal strips touching each other or by the weatherstrip fitting into a saw kerf in the wood.