Gate valves are suitable for full-on, full-off flow control.Turning the handle counterclockwise to raise the disc, allowing flow through a straight passageway. Turning the handle clockwise to lower the disc, impeding flow. Specification: Name: marine gate valve Material:cast iron , stainless steel , bronze , cast steel Working pressure: 5k, 10k, 20k, 40k Size:d n25 ~ dn800 Sandard: jis, din, gb Lead time: around 35 days Certificate: abs , bv , ccs , dnv , gl , lr , kr , nk , rina , rs