STM Bolt Size Tool (BST)

This simple gauge belongs in every tool box! Made from sturdy lightweight plastic, this allows you to size bolts, screws and nuts in USS, SAE and Metric and identify the thread pitch. Easily determine your bolt diameter by pushing it through the sizing holes.

Features:
• Excellent for sizing bolts, screws, nuts (USS, SAE, and Metric) and twist drills
• Size bolt diameter by pushing bolt through sizing holes
• Gauges hex nuts and washers (USS, SAE)
• Gauges metric hex nuts and washers by holding under metric holes
• Measure US and Metric thread pitch
• Special notch gauges flat headed metal and wood screws
• Ruler marked with inches and millimeters for worldwide use
• Resists water, alcohol, oil, and grease
• Reliable and Accurate
• Sturdy and Lightweight Plastic
• Compact Size (8-5/8 x 3-1/4")