Sink drain components are items that facilitate or enhance the proper functioning of a drain. They can vary from simple rubber plugs to bottle traps, which prevent bad smells from flowing back up through drainage pipes. What are sink drain components used for? Sink drain components are intended to aid the drain in its purpose of removing used water (or, in the case of sink plugs, to prevent water from escaping through it). In the event of a clog, these components must also accommodate the use of a plunger or drain auger (commonly known as a plumberâ€™s snake). Types of sink drain components. Different types of sink drain components include types of bottle traps, also known as P-traps or U-bends. Bottle traps help to maintain hygiene standards and keep drains odour-free. Water collects in the trap and provides a block that prevents gases and foul smells from flowing back up through our drainage pipes. Other sink drain components include sink plugs (including pop-up plugs as well as plugs that are simply inserted into the drain) and overflow-prevention devices.