The McAlpine MACTUN-2 is a combined tundish and non-return valve that provides a reliable and efficient solution for protecting against backflow in a range of plumbing applications. Like the MACTUN-1, it is the only combined tundish and non-return valve with a silicone membrane seal, ensuring that it will not be affected by hard water areas. The MACTUN-2 is made from high-quality materials that are resistant to corrosion and can withstand high temperatures. It features a silicone membrane seal that ensures a tight and reliable seal, even in hard water areas.