Swing check valves have a solid thermoplastic body with a large "flapper" that seats against the body of the valve. Swing check valves offer a large fluid area with a removable bonnet that allows for the valve body to be cleaned out without removing the valve from the pipeline. This is beneficial for installations that may contain debris or other items that could potentially clog the valve. Check valves are used in applications where it is essential to ensure fluid flow passes in only one direction. Check valves can be mounted in vertical or horizontal directions, with the only restriction being a minimum back-pressure required to properly seat the check valve. Spring assists and lever and weight mechanisms are available options to assist in closing the valve quicker to reduce water hammer concerns.