This nut and bolt has been upgraded to aluminum with red/blue oxide layer for each thread gauge, providing clearer size marks with anti-rust and anti-wear features that long-lasting visibility. [Blue Oxide Layer Aluminum for Inch Size] Includes 14 Inch size part numbers: 6-32, 8-32, 10-24, 10-32, 1/4-20, 1/4-28, 5/16-18, 5/16-24, 3/8-16, 3/8-24, 7/16-14, 7/16-20, 1/2-13, 1/2-20. [Red Oxide Layer Aluminum for Metric Size] Includes 12 metric sizes part numbers: -0.7, M5-0.8, M6-1.0, M7-1.0, M8-1.0, M8-1.25, M10-1.0, M10-1.25, M10-1.5, M12-1.25, M12-1.5, M12-1.75. [Nut & Bolt ] With 26 male/female gauges, included 14 inch & 12 metric sizes, our product is the ideal solution to all your nut and bolt checking needs. [Easy to Hang] Our nut and bolt gauge comes with a convenient hanging feature that allows you to hang it on a pegboard or tool rack for easy access. Inch (14 Sizes): 6-32, 8-32, 10-24, 10-32, 1/4-20, 1/4-28, 5/16-18, 5/16-24, 3/8-16, 3/8-24, 7/16-14, 7/16-20, 1/2-13, 1/2-20 Metric (12 Sizes): -0.7, M5-0.8, M6-1.0, M7-1.0, M8-1.0, M8-1.25, M10-1.0, M10-1.25, M10-1.5, M12-1.25, M12-1.5, M12-1.75 Note: Installation guide not included, we strongly recommend you professional installation. Please check as much as possible to make sure the item is what you need. Tips:The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use. Colour:As Shown Material:Metal Package Contents: 1 * Nut and Bolt Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.