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.
- Time checking (9th round)
- Message sending (7th round)
- Communication between wearers (2nd round)
- Storing weapons (1st round)
- Video recording/replaying (14th round)
- Containing items (e.g.toys) (11th round by zhong)
In the 25th Round, Dong Zhuo gives Lu Bu a new siman saying that it's a gift from father to son. In truth, the siman is encrypted with black energy, giving Lu Bu a dark version of his original weapon.
In the 32nd Round, Dong Zhuo uses the connection between their simans to take control of Lu Bu's actions, thus turns him into his slave temporarily. When Lu Bu discovers in 36th Round that his father is using the siman to keep track on him, he destroys it immediately. In addition, frees him from his father's hold.
- Siman is an O.D.M. watch used on the show as a communication device. (ODM DD101 & DD101A)
- Zhao Yun and Lu bu(after round 25) are the only male characters who wears a white Siman.
- Xiao Qiao is the only character who wears transparent Siman.
- Sun Shang Xiang and Da Qiao wear a black and Gothic-type Siman.
- While most people wear their Simans on their left wrists, Huang Zhong and Da Qiao wear theirs on the right.