Stenner: "operating pressures up to 25 psi or 100 psi maximum". Huh?

[Reach4]

https://stenner.com/select-right-stenner-pump several places says
"operating pressures up to 25 psi or 100 psi maximum".

What are they trying to say? I would think the injection point would usually be above 25 psi.

 

[Treeman]

I use a stenner pump in our workplace greenhouses at regular well pressures of 60 lbs. +/-. The only difference I can see in the 2 models is that the 100 lb. version comes with a duckbill check valve. There must be applications where the injector is used in systems under 25 lb. pressure where the check valve is not needed - eliminating an additional maintenance/wear item that might be missed and cause a malfunction?

https://stenner.com/products/parts/check-valves

The check valve is so cheap it seems silly not to just use it?:

 

[Sponsor]

 

[LLigetfa]

I would think the injection point would usually be above 25 psi.

Drip or soaker hose irrigation systems often are under 25 PSI.