Best Tap Drill Size Calculation

• Professional reproductions of original 1940's Atlas charts
• Professionally printed on 36 lb high resolution coated bond matte poster paper
• Suitable for framing
• Charts each measure 16 5/16" x 21 5/16"

• 90 degree V-groove along the bottom allows perpendicular alignment on round parts or corners.
• Eliminate tap breakage due to improper alignment.
• Automatically squares up the tap with the surface.
• Portable, pocket size

• Professional reproduction of original 1940's Atlas chart
• Chart measures 16 5/16" x 21 5/16
• Professionally printed on 36 lb high resolution coated bond matte poster paper
• Suitable for framing