Hach 2745650 pH Test Strips, 4-9 pH Units

I would recommend

Good product we use a lot in our Aquaponic system

Expiration dates are well valid up to 1 year, excellent.

The original order was shipped with expired products, only expired by a couple months but that’s not the point. Good news, as always Amazon corrected the problem and shipped me replacements right away.

Not very accurate. If you need just ballpark number it's ok but If you need an accurate number buy something else.