#120H heavy offset links are also commonly referred to as #120H half links. Offset links are commonly used for adding additional links into a roller chain. Offset links are good to have on-hand because they can keep you out of a down situation, and they are good for making miscellaneous repairs to the roller chain. These offset links exceed in quality, durability, and overall strength. General Duty Plus #120H Heavy offset links feature heat-treated components, solid rollers, and the side plates are Heavy Duty. These offset links are manufactured specifically for #120H heavy roller chain.