Diablo 1/4 In. SDS-Plus Mortar Knife. Diablo's SDS-Plus Mortar Knives Deliver Extreme Durability And Stability When Removing Mortar In Vertical Joints Of Brick And Block. A Unique Heat Treatment Process Strengthens The Steel Body To Withstand The Stress Of High-Powered Hammer Drills And The Impact Of Removing Mortar. The Precision Plunge Tip Accurately Plunges Deep Into Mortar For Superior Efficiency. Featuring A Sharp, Straight Edge, The Tapered Knife Cuts Away Mortar With Speed And Ease. Optimized For Maximum Performance In Corded And Cordless SDS-Plus Rotary Hammers.