Clejuso #8

This is a modern restraint, currently in production but also unique and very high quality. The ratcheting, non swing through leg iron by Clejuso sold for $100 with 2 keys after 1 bid. 

These are heavy, solid, and secure. They don't have a swivel but I have seen some which do. The double lock is finger activated at the corner of the lock case. 

They are listed for $115 on Handcuff Warehouse but are currently out of stock. 

These go well with Clejuso 13 or 15 handcuffs as well. They have a rather short chain and adjust tightly. Due to the shape of the cuff, these can be "comfortable" to wear when stationary but can also be painful when walking if the cuffs rotate around the ankles, so take shorter steps.