Using this tool is the best way to ensure accurate derailleur alignment, and prevent shifting problems
Screws directly into rear mech hanger threads
Gauge bar pushes gauge rod against the rear wheel
Measurements are taken at 6, 9, and 12 O' Clock positions
The tool is used to gently bend the mech hanger to the correct position
Made from heavy gauge steel, with a chrome plated finish
Updated over the longstanding DAG-1 the DAG-2 utilises a longer measuring pointer, longer threaded stud and a longer, narrower alignment boss to fit a wider variety of bikes
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As with any product, specification is subject to change without prior notification. You are advised to confirm current availability and specification before buying.