Requires 12 M4x12MM bolts and 14 M4 nuts to assemble.
Both sides are identical, they contains six different printed pieces and are assembled using five M4 bolts and five M4 nuts. The printed pieces are the two sides, the hook that closes around the wrist, the ratchet that grabs the hook when closed, a spring that pushes the ratchet towards the hook, a pin to keep the locking piece in its place, and a spacer to let the hook move freely and not be wedged between the two sides. The internal pieces are shown in the third included image.
The chain is connected to each side using one M4x12MM bolt with its head cut off and two M4 nuts. One nut is placed between the two main parts of each side of the handcuff and the other nut is placed in the end of the chain and the bolt with a cut of head is screwed into both nuts.