We stock a complete selection of I.S.O. standard chain from Acco to fit almost any windlass. All Acco chain is hot-dip galvanized, which is superior to the zinc electroplating used by most other major U.S. chain vendors. When comparing Acco chain to other brands, be sure to ask if other models are hot-dip. Remember that the Safe Working Load (SWL) is a conservative rating for safety and should not be exceeded, although the breaking strength is generally 3-4 times greater. Proof Coil (PC) is made of low-carbon steel and designed for ordinary marine applications, but not for use in most windlasses due to its long links. BBB is made of low-carbon steel, but has shorter, calibrated links that are designed to be compatible with many windlasses.