CrownCrete U™ Cove Base Product No. 811 is a three-part urethane polymer concrete Cove Base product. It is designed to withstand aggressive chemical attack, thermal shock resistance, and can be used as a patching materials. CrownCrete U Cove Base is an integral part of the CrownCrete U flooring family of products. The vertical portion can be installed to any height at 1/16" to 1/4" thickness.