1. With the rotating rod as the axis, it can be rotated 360 degrees, measure the distance between the rim and the tail hook, and correct the tail hook
2. Lock the swivel rod, precision thread, turn the handle clockwise, screw the swivel rod into the tail hook, precision lock
3. Lock and press the sliding bracket to adjust the distance between the measuring rod and the wheel hub, and measure the deviation between the tail hook and the wheel rim
4. Move the measuring rod to contact the rim, and then move the O-ring to align with the sliding bracket to locate
5. Material: aluminum alloy
6. Use: used for the calibration and correction of the tail hook on the bicycle
7. Weight: about 720 grams
8. Size: about 43x10.8cm