... 3.Environmental protection 4.Durable passive roof top Solar water heater with assistant water tank FEATHERS: 1. The material of the ... : assistant tank, electrical heater.8. 5 years warranty. MaterialEvacuated tubeHigh borosilicate glass, with aluminum absorption layer of magnetron ... Y=220-260./KWTotal Weight 87KGS87KGSCertifications Solar Keymark, SRCC, SGS, CE, ISO9001Warranty 5 years5 years