The tapered bore and integrated reservoir surrounding the piston (which is white, surrounded by a black O-ring, just behind the spring) are visible in this clear model of the Elixir master cylinder. The inside of the black, bell-shaped rubber bladder visible behind the piston is open to the air to equalize pressure inside the reservoir.
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The tapered bore and integrated reservoir surrounding the piston (which is white, surrounded by a black O-ring, just behind the spring) are visible in this clear model of the Elixir master cylinder. The inside of the black, bell-shaped rubber bladder visible behind the piston is open to the air to equalize pressure inside the reservoir.