A siman is a watch-like device with many special functions. It is first introduced in K.O.3an Guo. These devices are worn by almost every person in the Silver Dimension. Simans are divided in color, whereas males wear black simans and females wear white ones. Simans are also divided by materials they are made of. Males wear simans that made of rubber/silicone, while females wear simans that made of plastic.