Retainers (37) are exposed on an outer surface of the sub-housing (30) and are displaceable between a locking state for retaining terminal fittings (34) inserted into a sub-housing (30) and a separated state for allowing the terminal fittings (34) to be withdrawn from the sub-housing (30). A frame (10) is formed with a holding portion (20) configured to hold the sub-housing (30) by being locked to the outer surface of the sub-housing (30) and openings (24) expose the retainers (37) with the sub-housing (30) held in the holding portion (20).