The Straight-Fit backwater valve from Mainline Backflow has a flapper designed to smoothly guide cleaning and surveying equipment through the valve and allows for safe withdrawal, minimizing risk of damage to the flapper. The addition of a Smart-Curve snake guide prevents damage to the valve body during snaking from the main access. The valve body design has minimal slope, making it ideal for new installations and retrofits. 877/734-8671; www.backwatervalve.com.