Kore mega range expander sprocket shimanothe megarange cassette sprocket is designed to be coupled with the kore stronghold narrowwide chainring so you can simply change your 2x10 set up into a 1x10 set up at a super economical price this set up gives you a wide 1x10 gear ratio but eliminates the need for a front derailleur front shifter cable and inner chain ring thus making a substantial weight saving to your bike and at a fraction of the cost of a 1x11 set up features material al7075 t6