Features: The intermediate wire joint is made of red copper of high electric conductivity. There are seven kinds of copper joint tube from 2.2mm~6.5mm for different connection of different cords. The joint tubes are integrated in a box,portable and convenient to access and store. Compact and practical circular design makes it works more stable. These tubes are firm and strong,suitable for connecting electric cable. Specification:Material:CopperApplication:Electric CableConnection Type:AC/DCSize:2.2 x 12mm / 0.09 x 0.47in(for 1 square centimetre)2.5 x 12mm / 0.1 x 0.47in(for 1.5 square centimetre)3 x 12mm / 0.12 x 0.47in (for 2.5 square centimetre)3.5 x 12mm / 0.14 x 0.47in(for 4 square centimetre)4.5 x 12mm / 0.18 x 0.47in(for 6 square centimetre)5.5 x 12mm / 0.22 x 0.47in(for 10 square centimetre) 6.5 x 12mm / 0.26 x 0.47in(for 16 square centimetre) Package List:250 x Copper Joint Tube