An alignment gauge is essential for diagnosing and repairing bent or misaligned derailleur hangers, often the cause of shifting problems. The DAG-3 features a completely new design, engineered and built to be lightweight, precise, and versatile. The sliding indicator can measure derailleur hanger alignment against bicycle rims of any size and rotates to clear seatstays, racks, and other obstacles, allowing for 360-degree measurement. The long, precision-extruded aluminum body is built to tight tolerances and provides adequate leverage for making adjustments.