AQUA PRO CITY WATER FILLS - Recessed and surface mount models to fit all applications. Direct replacement for Marshall Brass and JR Products models. All Aqua Pro models are made of non-toxic materials, have ôpoppetö style check valves, 1/2" pipe thread and are certified to IAPMO and NSF standards. SURFACE MOUNT MODELS - Surface mount models are available in metal, plastic and aluminum. Metal is powder coated for a long lasting finish. Plastic is UV stabilized for durability. Aluminum has a ôbrushedö finish. Surface mount models are 3" outside dia., and require a 1-1/4" dia. cutout. Aluminum Surface Mounting Flange w/1/2" FPT. Bulk.