1. Size: DN50-DN700 2. Design as MSS-SP-81 3. F-to-F dimensions: EN558-1 SERIES 20, MSS-SP-81 4. Test: DIN3230, MSS-SP-81 KNIFE GATE VALVE, BI-DIRECTIONAL, PN10/CL1251. Size: DN50-DN7002. Design as MSS-SP-813. Face-to-face dimensions confirm to EN558-1 SERIES 20, MSS-SP-814. Test: DIN3230, MSS-SP-81