Advantages: Better distinguish the metric and imperial sizes, respectively made into different colors, silver represents the inch size, black represents the metric size
Easy to operate: You can screw the nut or bolt into the thread gauge to check the size, easy to operate
Convenience: 23 Inch & 21 metric thread gauges in a box, easy to carry, you can take anywhere you work
Design: The size is marked on each thread gauge as well as on the foam, so can quickly find the size you want and improve work efficiency