Handcuffs build with technic LEGO. Can open and close and a small click-on function can lock them into place. Use the “key” to click it open again. Since not all pieces are made in the same color from LEGO it is a bit of a mix of dark stone gray and medium stone gray. The red pieces is there to easily guide you to the key hole mechanism.
Original design:
BrickGuider.com
Parts list:
https://www.brickowl.com/wishlist/view/BrickGuider/handcuffs
Build instructions:
Handcuffs.pdf