The Shimano CS-9100 Dura-Ace 11-Speed Cassette is a super lightweight 11-speed HG-EV cassette with a rigid carbon and alloy carrier for excellent shifting even under the most demanding gear changes. The Shimano CS-9100 Dura-Ace 11-Speed Cassette's largest sprockets are mounted on lightweight alloy and carbon carriers to reduce weight and the 5 largest sprockets are made from titanium to reduce weight without sacrificing strength.
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