... of use (switch without people manual operation). 2. Connection type: flanged type, push-on type, mechanical joint type, plain ends type 3. Material: ... manufacture standard:ASME,EN,DIN,ISOconnection type:flange end,support lugPort type:through wayOperation type: manual operationflow direction: single ... check effect, also can be applied to various vertical shaft manhole cover; Only for one-way water ...