1. Precision Alignment: Effortlessly mount the bicycle handlebar saddle positioner at the center of the handlebars when the light aligns with the tire's center, you've achieved the perfect adjustment. 2. Versatile Use: Designed for multi-purpose adjustments, this bicycle calibrator is your go-to for aligning handlebars, saddles, and more, ensuring your bike is set up for optimal performance. 3. Construction: Built to last, this bicycle handlebar saddle calibration device withstands the rigors of regular use, providing a reliable solution for maintaining your bike's alignment over time. 4. Effortless Setup: Say goodbye to the guesswork and strain of aligning saddles and handlebars by eye this handlebar saddle positioner simplifies the process, ensuring a straight and comfortable ride every time. Colour:Black Material:Plastic note:3 x button batteries not included Package Contents: 1 x Bike Handlebar Calibrator Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.