All parts are included in the Lifegard bulkhead kits. No costly extra fittings to buy or not have on hand when needed. Safer: Lifegard heavy wall bulkheads are constructed of the highest impact resistant pvc. It eliminates the possibility of finding hidden cracks when filling the aquarium. Versatile: Lifegard bulkhead fittings are designed so the suction screen just presses into place. Requires 1 3/4" hole.