Medallion Pools ICFG1442 Inside Corner Filler for 42" Walls 14ga Galvanized Steel - Create the inground pool of your dreams with this Medallion Pools Inside Corner Filler for 42" Walls. It is constructed of durable 14-gauge galvanized steel. Steel is an ideal choice for inground pools due to its natural malleability. Steel is able to handle changing conditions while remaining strong and intact.