Heliodyne model GOBI 408 solar collector panel for domestic hot water applications featuring aluminum absorber with blue sputterabsorber coating on surface. Factory unions installed for easy installation. Fluid passageways and header is all copper. Size is 4' X 8', 29.83 square feet absorber surface. Black anodized extruded aluminum frame with low iron tempered glass. 10 year warranty. This item is especially suitable for areas with severe winter climate or for use in space or radiant heating.