AI1113 pH Calibration Buffer Solution Kit (7.00, 4.00), 8 oz. Each

Seems to work well

These are the go-to reference solutions for testing the acid levels in wine. This brand has a 2-year expiration date. The coloration of these references makes it easy to not mix them up.

My only gripe is that it smells very strongly of wintergreen. Your instrument will smell of wintergreen even after you rinse it, meaning something is left coating your sensitive and highly expensive ph meter. This doesn't seem to impact performance however. And other reference materials are not as fairly priced, so its a good buy. My bottles arrived leak-free and were packaged well. I would reccomend this product as long as you can stand the minty-fresh smell that hangs around on your instrument for several days. Atleast it smells fresh i guess!

Only thing to use for April 20

Works fine but package had been used or damaged in shipping because 7.00pH bottle was missing 20% volume and tested off on my already calibrated pH meter.