EF7000-QA Everflo 12V Diaphragm Pump w/ Quick Attach Ports shipclass=85 Throttling valves are for regulating

Throttling valves are for regulating flow in systems equipped with centrifugal pumps where sensitive regulation is required or to control flow in jet agitator return lines

04 Valve Assembly

While it is a manual reel

Model:  7802-301 - 12 VDC Automatic Demand with On/Off Switch

and if you do not have a pump that includes one

EF7000-QA Everflo 12V Diaphragm Pump w/ Quick Attach Ports shipclass=85 Throttling valves are for regulatingDesigned by Valley Industries in Minnesota, the EF7000 QA is Everflo's most powerful diaphragm pump. Solidly enclosed yet affordable, it's ready to install in your existing or new agricultural, lawn, RV or marine sprayer. Replacement parts and easy to follow diagrams are available for you to get the most out of your investment.