10" RIV Cast Iron Knife Gate Valve Unidirectional For Lever Operation AGRI Standard and PN10. RIV120The 10" RIV Cast Iron Knife Gate Valve is designed for lever operation and meets AGRI Standard and PN10 specifications. Its unidirectional flow ensures optimal performance, making it ideal for agricultural applications. With durable cast iron construction, this valve provides reliable and long lasting operation. To suit PN10 and AGRI Standard Square Flanges 4 Hole Cast Iron Body Stainless Steel Blade NBR Gaskets Fully Enclosed for Safety, with