The Fowler-Bowers XT Analog Bore Gages offer an economical solution to accurate shop floor bore measurement. Fast, accurate and easy-to-use, the wide application range of the XT Analog Bore Gage line may be purchased individually or in sets. Included in this set are the following items... .375" - .500" Measuring Head & Handle .500" - .625" Measuring Head & Handle .625" - .750" Measuring Head & Handle 2 Setting Ring