Folding bicycle integrated 7-speed cassette for brompton Flywheel 7 speed Chrome Moly Steel 11T/13T/15T/18T/21T/24T/28Ttensioner Folding bicycle integrated 7-speed cassette for brompton Flywheel 7 speed Chrome Moly Steel 11T/13T/15T/18T/21T/24T/28Ttensioner. Sale price : $98.56 Category : Sports & Entertainment