This kit works great and is easy to use. It comes with a battery operated stirrer so swirling is very easy. I primarily use this when shocking, since an oto comparator is cheaper/easier for daily use.

The fas-dpd test really is the most accurate chlorine test you can get.

I no longer need to squint at a color bar that is hard to differentiate 1. Add the indicator powder and stir to mix, then add the reagent dropwise. No more tying to match up the colors on a chart.

This is the fourth setup i've purchased for the purpose of testing spa water for chlorine. The residual of free chlorine lets you know you are feeding enough to get the maximum effect.

At this time, i have no reason to think this kit isn't as accurate as the manufacture claims. The epa has certified the accuracy of the the test strips.

Received this item in a middle of may 2022. Expiration date is septemeber 2022. The instructions are very limited and no reference ranges are provided as with other kits.