The easy shifting cogs of this lightweight cassette offer strength and precise shifting while the powerglide ii technology means the sram pg820 8spd cassette is both reliable and durable features regular black cog 8 speed cassette easy shifting powerglide ii cogs gear ratio 11 32 11 30 drilled cogs save a few grams sprocket material durablast lock ring material steel speeds 8 speed recommended chain pc 38