A canister, mounted in a vehicle with an engine and including one or more chambers, includes adsorbents, an inflow port, an atmosphere port, an outflow port, and an adjusting member. The adjusting member is placed in a target chamber of the two or more chambers together with a corresponding adsorbent of the adsorbents. The target chamber is provided with a cushioning area located adjacent to at least one port of the ports. Two or more rod-shaped portions have first and second cross-sections orthogonal to a flow direction of an atmosphere and a fuel vapor. The first cross section is formed in the cushioning area, and the second cross-section is formed at a position distanced from the at least one port relative to the cushioning area. The first cross-section has a smaller area than an area of the second cross-section.