Wall Mounted Thread Checker Quickly identify the most common size nuts & bolts in one easy-to-display center! Starting from the top you have 28 female threaded holes to identify common inch & metric bolt sizes, following that you"ll find 28 male threaded studs to identify nut sizes and at the bottom you"ll find screw diameter & bolt length checkers. Mounted on heavy-duty 1/2 Inch Sintra board and predrilled for easy installation, the Wall Mounted Thread Checker is ready to start saving you time and money by ensuring you have the right fastener for the job - the first time! The Wall Mounted Thread Checker, also known as a Thread Verifier or Thread Identifier is a great addition for any Home, Hobby, or Inventor"s Work Shop; Auto, Motorcycle, Marine, ATV or RV Repair Shop; Heavy Equipment Repair Shop, Military Equipment Repair Station, Machine Shop, Fabricating Shop, Assembly Department, Production Department or Quality Inspection Station! SWTC-WM1 Size Specifications: INCH: 6-32, 8-32, 10-24, 10-32, ¼-20, ¼-28, 5/16-18, 5/16-24, 3/8-16, 3/8-24, 7/16-14, 7/16-20, ½-13, ½-20; 9/16-12, 9/16-18 METRIC: M4x0.7, M5x0.8, M6x1.0, M7x1.0, M8x1.0, M8x1.25, M10x1.0, M10x1.25, M10x1.5, M12x1.25, M12x1.5, M12x1.75 Made in USA!