It is exposed to extreme loads and weather conditions. Chains stretch at different rates depending on the usage conditions, but each must be replaced sooner or later. Timely replacement of the chain is the only way to protect the chainrings and sprockets from excessive wear. To maintain the best possible performance of the Shimano HyperDrive System, it is important to use original Shimano HG chains. Intended use: derailleur gear. Type: chain. System compatibility: 7-speed.