Use 3/32" chain when both chainring and sprocket(s) are 3/32, as found on all new Brompton's. SRAM PowerLink. 98 / 102 Links. 98 Link length for use on a 2/6spd with a 44T front chainwheel and either the 12/16, 13/16 or 13/15T combinations of rear sprockets.
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