Dometic 12 Holding Tank – Horizontal Install The Dometic Holding Tank is leak proof, constructed with 6.3 mm thick walls and a highly sturdy polyethylene design for odor free use. To prevent potential leaks the holding tank uses top mounted fittings and dip-tube discharge plumbing. In order to eliminate the need for complex plumbing and extra discharge line connections the 12 HD Tank features multiple discharge outlets. It also features the vacuum relief valve that prevents damage from high capacity dockside vacuum pumps. Leak-proof design Two separate outlets for overboard and dockside discharge Odor-free design avoids unwanted smells Pre-installed and tested fittings can rotate giving users flexibility Durable 6.3 mm thick corrosion-resistant polyethylene walls (ISO/USCG compliant) 57 l (15 gal.) waste capacity Vacuum relief valve prevents damage from high-capacity dockside vacuum pumps Specifications: Dimensions Depth: 22″ Width: 19″ Height: 15″ Weight: 21 lbs