A filter element comprises a filter media and a restriction indicator device. The restriction indicator device comprises an attachment portion and a movable portion. The attachment portion is attachable to a portion of the filter assembly. The movable portion is movable relative to the attachment portion between a non-buckled position and a buckled position. The movable portion moves from the non-buckled position to the buckled position once a predetermined pressure drop between an upstream side and a downstream side of the movable portion of the restriction indicator device is met.