The Fowler 52-470-000-0 is another great tool for easy and accurate measurements. Under spring tension, the plungers of the gage expand from the center to the size of the hole being measured and are then locked in place using the knurled knob. Final hole size is obtained by measuring over the contacts with a micrometer or vernier caliper.

• Contact points are constructed of hardened tool steel, precision ground.
• 52-470-000-0 features Titanium coated points for consistent accuracy and increased durability.
• Double action rigid handle with self-centering feature for quick checking of inside measurements.
• Constant spring tension for uniform feel.
• Covers a measuring range of 5/16” to 6” with measurable depths of 4” to 5”.
• Includes fitted vinyl case.