This jacket makes a significant difference when comparing the efficiency of the Robobrew units and it’s a jacket that will pay itself off in energy saving so it's a good option to any new Robobrew User. 10% faster heat up time, 50% less heat loss from the boiler. The one jacket size fit’s both BrewZilla / RoboBrew 35L & our DigiBoil 35L. The jacket is made from thick neoprene which is easy to hose down after use.