Bow gauge is a three-point contact gage equipped with a dial indicator or digital micrometre. The gages feature a protruding plunger which measures the peak-to-valley depth of the surface.

The flatness tester can quickly and easily measure the uneven defects on the surface of flat glass, especially for the glass reinforcement testing of tempered glass.

The instrument is small and easy to carry. It can be used for real-time detection at anytime, anywhere, regardless of size. Any flat surface can be measured by using this gauge.