Bus ribbon is a very specialized interconnect for photovoltaic modules. Much like tabbing wire (ribbon) bus ribbon is made of a copper ribbon or flat wire which is coated in solder. The solder protects the surface of the copper from oxidation and provides a layer of solder to form a solder joint. These solder-coated copper strips are used to channel current from the top and bottom of solar cells (tabbing/stringing) or to collect the electricity from these strings (bussing). The main difference: bus ribbon is a bit wider, and sometimes thicker than tabbing ribbon. You can think of tabbing wire as roads which travel across a solar cell, and bus ribbon as the highways that connect and tie them together. Bus ribbon is larger in cross-section because it has more electrical current to carry. Specifications:GAUGE: 0,15200MMWIDTH: 5,0000MMUS SIZE: 0.006" X 0.1969"MATERIAL: 96.5SN/3.5AG HOT DIPPED COPPERSOLDER COATING THICKNESS: 410-600 MICROINCHES/SIDE