配套 means 'to form a complete set' — it describes parts designed to go together as a whole system (e.g., furniture set, compatible software). This differs from 搭配, which is about actively pairing or coordinating items like clothes or food, and from 匹配, which is more formal and often used for technical compatibility or romantic suitability. 配 is a simpler, all-purpose 'to match' covering many contexts.