Canister

A canister configured to be mounted in a vehicle with an engine, the canister comprising:

• two or more chambers in which an adsorbent configured to adsorb an evaporated fuel is placed;
• a case forming a main chamber, the main chamber being one of the two or more chambers;
• an inflow port, the inflow port being a part that is provided to a first end of the main chamber and configured to cause the evaporated fuel to flow from a fuel tank of the vehicle into the main chamber;
• an atmosphere port configured to be open to atmosphere, the atmosphere port being provided to an auxiliary chamber, and the auxiliary chamber being one of the two or more chambers;
• and
• an outflow port, the outflow port being a part that is provided to the first end of the main chamber and configured to cause the evaporated fuel adsorbed on the adsorbent to flow out towards the engine by utilizing the atmosphere flowing in through the atmosphere port,
• the case including at least one reduced part that is a wall-like part forming an area in the main chamber in a vicinity of the first end, and
• the at least one reduced part being configured such that an area of a cross-section of the main chamber orthogonal to flow directions of a fluid is reduced towards the first end.