Bowers XT Analogue Standard 3 point micrometers 20-25mm XTA20MBowers XTA Standard Analogue Bore Gauge This bore gauge set from Bowers Group, complete with setting ring, includes the XTA Micro Analogue bore gauges. These bore gauges feature a more compact mechanical controller which is lighter and more ergonomically designed. The XTA Micro's Vernier scale improves resolution from 5 to 2. FEATURES More compact mechanical controller Lighter and ergonomically designed Improved functionality Vernier scale added to