Universal valve must be used and can choose to use logo items, as shown in the table. For manual valves, if the hand wheel size is large enough, then there should be instructions on the hand wheel valve closed arrow or additional "open" "off" message. Plug Valves Universal Valve logo items (GB12220): Nominal diameter (DN); nominal pressure (PN); pressure parts material code; manufacturer's name or trademark; media flow arrows; sealing ring (pad) Code; limit temperature (