SeqLite Shimano Ultegra Dura Ace 11 Speed Compatible Alloy Road Cassette

These appear to be very fragile, but they aren't at all ! These are awesome, super light and really trick! I ride 42 miles every other day and lift weights on the other day. I have three of these 2 on bikes and 1 spare. If you use these as mentioned: keep as clean and lubricated as possible they are fine. But if you aren't clean or meticulous the they might not work for you . I even have some Dura-ace cassettes, but I prefer these SeqLite ones.