It also has same two layers of copper conductor like Double layers MCPCB, but the metal core is in the middle of two conductor, so there're conductors (trace) on both sides of metal core, and were connected to each other by Vias. So we named it "Double sided MCPCB", and you can populated SMD on both top and bottom. Base material: Aluminum/Copper/Iron Alloy Thermal Conductivity (dielectrial layer): 0.8, 1.5, 2.0, 3.0 W/m.K. Board Thickness: 0.5mm~3.0mm(0.02"~0.12") Copper thickness: 0.5 OZ, 1.0 OZ, 2.0 OZ, 3.0 OZ, 4.0 OZ, 5.0 OZ Outline: Routing, punching, V-Cut Soldermask: White/Black/Blue/Green/Red Oil Legend/Silkscreen Color: Black/White Surface finishing: Immersion Gold, HASL, OSP Max Panel size: 600*500mm(23.62"*19.68") Packing: Vacuum/Plastic bag Samples L/T: 10~15 Days MP L/T: 12~15 Days