The Apollo® CVBE "Soft Seat" check valve offers reliable tight shut-off protection against reverse flow and corrosion resistance using proven ASTM quality materials made in the USA. Ideally suited for potable water, hydronic heating, and other low flow applications. Soft seat allows more resistance to vibration and may be installed in both horizontal and vertical upward flow applications. Bubble-tight shut-off, ideally suited for gaseous service. EPDM check disc (standard). Straight-through flow minimizes pressure loss. 1/2 psi cracking pressure. Made in the USA.