AYLIFU 3/4Inch Black Irrigation Venturi Fertilizer Injector Tube Venturi Fertilizer Mixer Injector for Outdoor Garden Agricultural Irrigation Equipment Tools

Great product!

The arrow is backwards that indicates flow. It will never work if used as labeled.The threads are labeled as "BSP" but I think they are straight-BSP; standard American garden hose fittings seem to work best. Standard tapered 3/4 NPT also sort of works but I didn't want to risk it.It is surprisingly sturdy, I had to do a lot of pushing and pulling on it for my installation and expected it to break but it did not.Creates a lot of suction even with relatively small amounts of flow. Will easily pull fluids in uphill. I did notice that if you are testing this without anything connected to the outlet the suction for the venturi isn't very strong; if you add a length of hose to the end it seems to work much better.There is a small simple one-way valve in the venturi. It is easy to remove and clean.Great deal compared to what else is out there. If the arrow pointed the correct way and it used NPT threads it would be five stars.

I installed this item assuming the arrow embedded in the plastic indicated the direction liquid should flow through it. Turned on the water and there was no suction. After puzzling on it for a while, and remembering some high school physics, I realized the arrow was wrong. Reversed it and it worked great.