upperworks [1]
Small equipment and accessories on a boat’s deck especially for rigging, adjusting and handling the sails.
turnbuckle 
Instrument for adjusting the tension of a rope; it is made up of a hollow cylindrical body with a threaded shank screwed onto each end.
winch 
Small crank for heaving a rope tight; it usually has a ratchet preventing it from rotating in the counter direction.
shackle 
U-shaped part that closes with a threaded shank; it is used especially for joining two chains or for attaching ropes.
snap shackle 
Metal ring that closes automatically with a spring; it is used to attach various elements such as sheets and sails.
hank 
Hook that is kept closed by a piston mechanism and set on a shank, which rotates on a ring; it prevents the ropes that are attached to it from twisting.