- Letter drill sizes A through Z
- Standard decimal diameters
- Range: .234" – .413"
- Easy-to-read size markings
- Useful for machinists, mechanics, fabricators, metalworkers, and DIY projects
- Ideal for checking and identifying letter-size drill bits
This Letter Drill Gauge is a handy reference and sizing tool for identifying standard A–Z letter-size drill bits. It provides quick and easy measurement of drill diameters from .234" to .413".