Park Tool Derailleur Alignment Tool. We have found this one to be the best, and it comes at a fair price.
The DAG-2.2 is an indispensable shop tool that can be used to both measure and straighten misaligned derailleur hangers solving a high percentage of shifting problems
- Gauge bar made of heavy gauge, chrome plated steel
- Adjusts to fit 20” to 29”+ wheels
- Replaceable threaded tip
- Upgraded, large inner shaft for added strength
- Tighter tolerances for improved accuracy over previous models
- Improved clearance and reach to fit more frame/hanger combos including low clearance thru axle derailleur hangers