Stone Edge Surfaces CPR-Concrete Patch and Repair is a just add water, high-performance, multi-use, fast-setting (15 - 30 minutes), structural strength in 1 hour, high psi, no-shrink Concrete Patch and Repair material used for general and structural concrete repair from feathered edge to 4” thick. CPR is a polymerized concrete that can be troweled vertically, horizontally or overhead, has superior bonding strength and bonds to almost all concrete surfaces. CPR can be used in industrial, commercial and residential concrete repair, patching, rebuilding concrete corners and stairs, block fences, brick, walls, pillars, and can even be applied under water. And, unlike competitor products…CPR does NOT require a Primer and does NOT need water curing.