A heater treater coated with Sherwin-Williams Heat-Flex® AEB - a sprayed thermal insulative coating that replaces traditional insulation to prevent corrosion under insulation (CUI) on hot process assets. Heat-Flex AEB rivals thermal retention capabilities of traditional insulation systems for a more sustainable approach to insulating assets With Heat-Flex® AEB, the highly costly and dangerous phenomenon of corrosion under insulation (CUI) could be a thing of the past.