●Manual Operated with No Batteries Required: No need to worry about battery failure or running out of battery. You can use it anytime, ●[Made of High Quality Stainless Steel] This product is a tire groove measuring gauge made of high quality stainless steel. Durable construction with excellent impact resistance, dustproof performance, rust protection, and so on to last a long time ●[Compact] Lightweight and small design that can be placed in your pocket, easy to measure even in narrow places. Comes with a clear storage bag for easy storage and transport ●[Easy to Handle] Place the reference and depth bar on a flat surface and press down the measuring groove until the depth bar is aligned with the measurement groove and you will see the measurements immediately. Very convenient ●If you have any problems or concerns that may be damaged in 1 year from the delivery process, please feel free to contact us. Our store is the exclusive seller of "SCITOOLS", but please be aware that the "SCITOOLS" digital verniers purchased from other stores are not authentic