Marshalltown 20" x 4" Finishing Trowel with Aluminum Alloy Mounting and Highest Grade Spring Steel Flexible Blade. A professional-grade tool designed for finishing concrete, hand floats, and bull floats, it features a high-grade carbon spring steel cross-ground blade that is fully heat-treated for strength and durability. The aluminum alloy mounting is polished and machine finished to ensure a perfect handle-to-post fit. The 'Diamond Shank' fits ideally into a square hole of Dura Soft handle for comfort and grip. This trowel is ASTM Specified, NIOSH, OSHA Approved, Federal Spec TT-P-1411A, TT-C-555B, and backed by a 10-year limited warranty.