1The surface of the telescopic rod is smooth, the curvature of the probe is good, and the result is more accurate 2With diamond nonslip handle, it will not slip during using, making measurement more convenient 3The tail is equipped with a locking device, CW to tighten, CCW to loosen, easy to operate 4Including 4pcs different type bore gauges, which can meet different needs for accurate readings 5High quality material can make sure the durability and stability of the product Item Type: Bore Gauge Measuring Range: Approx. 3 ~ 13mm / 0.1 ~ 0.5inHow to Use: 1. Loosen the inner hole gauge and put in the object to be measured2. Tighten CW, rotate one turn to ensure tightness3. After the measurement is correct, tighten the lock CW4. After locking, measure the inner diameter data with a caliper .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; } 1 x A-Type Bore Gauge1 x B-Type Bore Gauge1 x C-Type Bore Gauge1 x D-Type Bore Gauge