A single sliding window as a fitting (1) includes a first sliding member (51) attached to a rail outer surface portion (401), second sliding members (52A, 52B) attached to a rail inner surface portion (403) , And a pulling element (54) and recessing elements (55A, 55B) attached to an upper rail (211). When a window wing (4) is in a closed position, protruding parts (512, 542) of the first slider (51) and the traction element (54) are positioned to face each other in a direction outward of the plane of the window wing (4) , And protruding portions (522) of the second sliding members (52A, 52B) and the recess portions (552) of the recess members (55A, 55B) are positioned to oppose each other in the plane outward of the direction of the window vane (4). When the window wing (4) is closer to an open position than the closed position, the protruding portions (512, 522) of the first sliding member (51) and the second sliding members (51A, 2B) are positioned to face the upper rail (211) in the direction outside the plane of the window vane (4).