Starrett 20-3 Master Precision Square 3-Inch Blade Machinist Square

The Starrett 20-3 Master Precision Square is a professional-grade, hardened and ground steel square engineered for the most demanding layout, inspection, and toolroom applications. With a 3-inch blade, this compact precision square delivers exceptional accuracy in a size ideal for close-tolerance work on small parts, dies, molds, and machine setups.

Starrett Master Precision Squares are manufactured to close tolerances and feature hardened, stabilized, and precision-ground blades and beams, ensuring lasting accuracy through years of professional use. The blade and beam faces are ground square to within extremely tight angular tolerances, making this square a trusted reference tool for machinists, toolmakers, and quality control professionals.

Key Features:

• 3-inch blade length — ideal for small-part inspection and layout work
• Hardened and precision-ground alloy steel construction for durability and long-term accuracy
• Beam and blade ground square to extremely close tolerances
• Compact size suitable for toolroom, die shop, and bench work
• All faces and edges finished to a high degree of flatness and squareness
• Made by Starrett — a trusted name in precision measurement since 1880

The Starrett 20-3 is part of the renowned No. 20 series of Master Precision Squares, widely used by professional machinists and quality inspectors who require a reliable and accurate reference square for critical measurement tasks.