Custom installation is simplified and made more secure with included kits. PVC with the highest impact resistance makes up the heavy wall bulkhead, eliminating any chance of discovering a crack when filling the aquarium. LIFEGARD® Multi-Purpose Bulkhead Fittings come in jet black, matching most acrylic tank backgrounds. Each kit comes with the bulkhead fitting, gasket, and lock nut. Specifications: flange side is threaded, bottom side is threaded,