The universal RV holding tank fittings kit includes Uniseal seals, which are designed for reliable, watertight connections on black and grey water tanks. The kit features barbed pipe fittings that match the Elkheart brand fittings you referenced, ensuring full compatibility with your existing RV plumbing setup. This kit is ideal for adding or replacing fittings while maintaining a consistent, high-quality seal and connection across your RV's holding tank plumbing.