Description Applied With Standard Caulking Gun For Tuck-Pointing And Sealing Mortar Joints In Brick Or Block Surfaces, And For Repairing Cracks In Concrete Or Block Walls. Square Applicator Tip Designed For Mortar Joints. WARNING: This product can expose you to chemicals including Lead which is known to the State of California to cause cancer, birth defects or reproductive harm and Butyl Benzyl phthalate (BBP) which is known to the State of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov