Asayu 10Pcs Stainless Steel Single Way Air Valve One Way Valve Distributor Splitter for Aquarium Pump

It appears that regardless of the seller, or the configuration of the valves 1,2,3 .. they are all the same, and come from the same factory, just different vendors and prices. In spite of the sellers calling these valves stainless steel, they are all plated brass. We need to machine the end of the valve for a special vacuum application, and, indeed, our lathe tray is full of brass chips. If you are using these valves for air, vacuum, or non-aggressive gas, then not being stainless steel probably makes no difference to you. If you are using them for other chemicals, be warned, and test them first. As for the tightness, I think the valve is plated after assembly and the plating sometimes interferes with the valve's turning. We just tap the valve stem, not the turn handle, from both directions with a small hammer and ususally the valve becomes free. We have purchased over a hundred of these 'typical' valves and in spite of the small issues, they are a good value and performer.

Smooth action and precise control. Very sturdy. Highly recommend for the aquarist who uses air both to oxygenate and for ph control.

3 out of the 10 valves were defective right out of the bag...frozen in the wide open position. I broke one off trying to move it. The ones that work, work well.

Slightly larger than I am used to, but I actually find this beneficial. Highly recommend

I was lucky if 6 out of the 10 worked as they should. At least 4 of them I had to use pliers to turn the control lever.

This was just what I needed. Works great

Unfortunately none of mine will shut off.