Jyugo Manacles from Nanbaka

I'm making prison manacles for my son's Halloween cosplay. He wants to be Jyugo (Juugo?) from the Nanbaka anime series. In the picture he gave me, they're basically plain black cylinders, so I try to design as close to that as possible. Having them removable is the challenge, I've decided to go with hidden clips so two halves can snap together. A hinge design would have too many lines that don't exist in the cartoon.

So far I have the wrists done. Others to follow soon. Comments welcome