MIFAB® Series MI-DU trap seal primer distribution unit is engineered to receive a metered amount of water from a trap seal primer and distribute the water equally to either two, three or four floor drain traps. Choose from either 1/2 or 5/8 in compression connections by indicating suffix (-500) or 1/2 in or suffix (-625) for 5/8 in. The lid of the distribution unit has the numbers 2, 3 and 4 in marked on it. The body of the distribution unit has a guide marker on the top of the body. The numbers and the guide marker are positioned by removing the three screws in the lid of the unit and rotating the lid to match the appropriate numbers with guide marker to provide priming for the desired number of drains. The underside is marked with numbers one to four for ease in determining which ports will receive the water. Do not over torque the three lid screws when securing the lid back to the body. It is not necessary to install MIFAB® distribution perfectly level. The unique design will distribute water uniformly when out of level up to 5 deg.