A connector (10) includes a first housing (12) made of synthetic resin and including a fitting (11), and a second housing (14) made of synthetic resin and including a tubular receptacle (13) into which the fitting (11) is to be fit. At least one first projection (37) projects forward on a front end part (40) of the fitting (11) in the connecting direction and at least one second projection (43) projecting toward the first projection (37) is formed on a part of a back wall (27) of the receptacle (13) corresponding to the first projection (37). A fitting depth of the first and second housings (12, 14) is specified by the contact of a tip (38) of the first projection (37) and a tip (44) of the second projection (43) when the first and second housings (12, 14) are connected properly.