The Cla-Val 582 Series Two-Door Wafer Check Valve has torsion springs that force the two doors to shut before flow reversal, reducing the water hammer potential that normally occurs with single-door swing check valves.  To help reduce water hammer, the two-door design also reduces the travel distance from open to shutoff for a quicker response.  Extremely short in lay length, the valve is both a compact and an economical solution.