Moves sail clew  inboard while tightening the leech. Closes the slot.
Haul
Ease
Tightens the foot. Flattens the sail.
Moves the Clew outboard. Opens the Slot. Twists out the Leech.
The Barber Hauler gives you ultimate control of the position of the clew - thus the slot and the leech tension.
Sheet-in
Tightens the Leech. Similar to moving the car forward.
Play Again
Twists out the top of the Leech. Similar to moving the car aft.
Twists out the top of the Leech