The shimano cn4601 tiagra 10 speed chain a super narrow hyperglide hg series 10 speed compatible directional chain recommended for tiagra drivetrains the chain uses a directional design with specifically shaped inner and outer plates to optimise shifting over the chainset and cassette shimano cn4601 tiagra 10 speed chain features outer plate design has been developed to reduce the chance of chain suck the inner plate has been developed for better contact with gears providing smooth