Chains are versatile and great to use to restrain ankles. You can easily change size and use the same chains with or without boots on. If you have cuttingtool witch you should for safety you can have different length between the ankles. There are different thickness of chains to choose from and they are cheap. Chains dont have sharp edges so more friendly for you skin and nerves. My experience is that medieval ankles shackles vill be really painful especially when you start wallking. So a lighter chain can be better if you plan to walk a lot.