These are sockets (hook-type connection, not for lighting rails) that were used for system lights. The black socket parts are plastic, and the white ones are ceramic. This is a set of two white and one black socket. Both the cables and the socket parts are clean, with no noticeable dirt. 〈Specifications〉 Length approx.: White 50cm, Black 47cm For E26 type bulbs, for hook ceiling 6A 250V Bulbs not included Accessories not included ※Please refrain from purchasing if you are sensitive to scratches or dirt.