HFS(R) 6 PCS Precision Telescoping Gage Set 5/16'' - 6'' Range T-Bore Hole Gauges w/Pouch

[MATERIAL]: It is made of carbon steel with chrome plating on the surface [PACKAGE INCLUDE]: Range: 5/16" - 6" (8mm to 150mm),6PCS in total(1 gage: 5/16 - 1/2" range x 4.20" overall; 1 gage: 1/2 - 3/4" range x 4.40" overall; 1 gage: 3/4 - 1-1/4" range x 4.40" overall; 1 gage: 1-1/4 - 2-1/8" range x 5.85" overall; 1 gage: 2-1/8 - 3-1/2" range x 5.85" overall; 1 gage: 3-1/2 - 6" range x 5.85" overall); Ethylene plastic bag packaging [OPERATION METHOD]: Use the gauge to expand in the hole to be measured, lock it in place, and then take it down, and measure with micrometer or caliper to determine the final hole size [HIGH PERFORMANCE]: The rigid handle and double acting design (automatic centering) can quickly check the internal dimension. The spring tension is constant and the hand feel is even [APPLICATION]: It is used to obtain the exact size of holes and slots, which is suitable for factories, schools, offices and other places