It is designed to compensate for the volume of coolant that increases when heated. Designed for all models of liquid heaters. Maximum pressure 0.5bar.Compatible with Webasto : BBW 46 , BW 80 , DBW 2010 , DBW 2010 Sensoric , DBW 2012 , DBW 2012 Sensoric , DBW 2016 , DBW 2020 , DBW 2020 Sensoric ,..