The shimano hg41 8 speed cassette 11 30t the hyperglide sprockets have a computer designed tooth configuration with contoured shift gates resulting in a crisp smooth shift even under load shimano hg41 8 speed cassette 11 30t features high quality 8 speed cassette hyperglide sprockets have a computer designed tooth configuration with contoured shift gates resulting in a crisp smooth shift even under load gearing gives a low 30t sprocket making it easier to climb even the steep