The Sandvich, known in full as the Sandvich Edible Device, is an unlockable secondary weapon for the Heavy. It is half of a sandwich made with two triangular slices of bread. Between the slices of bread are lettuce, tomatoes, Swiss cheese, and an indeterminate meat that is referred to both ham and bologna by the Heavy. It is topped with a green pimento-stuffed olive pinned to the Sandvich by a toothpick.
The Sandvich can be consumed by pressing either the bound primary fire or taunt key. When eaten, it will replenish an amount equal to the Heavy's maximum health over a four second duration with no overheal. While the Heavy is eating, he makes a loud munching sound and the player is forced into the third-person view. As eating the Sandvich is considered a taunt, it cannot be consumed in instances when taunts can not be used, such as when underwater. The Sandvich will not have to recharge if the Heavy is already at maximum health, allowing it to be continuously consumed for leisure. - tf2 wiki