Pentair R161046 No.1 OTO Solution, 8-Ounce

This is a godsend for pool monitoring. The little bottles are so expensive by comparison. Definitely buy an eye dropper bottle when you purchase this because some of the little bottles in the testing kits are not refillable.

WHAT A FANTASTIC VALUE!I have paid $7 for a 1 oz. bottle of OTO before. This bottle is huge. I tested the chlorine in my hot tub with this and compared it to my old little bottle of OTO and both tests came out the exact same color.This is a great buy and I would buy it again, although I won't have to for a very long time.

Buying this much at such a low price has me testing more often and getting a better understanding of what is affecting Cl level.

I’ve read other reviews, complaining that this doesn’t come with a dropper mechanism, this was designed to be a refill bottle only , keep your empty old bottle, and use this to refill it

Its the same chemical, which works the same as any other. Just know that you need to get an eye dropper to use with it.

Economical way to replace an empty #1 pool test kit for chlorine pools

High quality product, cost effective, fast shipping.

The cost savings is huge compared to buying the same solution in 1 oz or 1/2 oz bottles. Another reviewer complained, correctly, that it does not come with a dispenser to easily put three small drops in your chlorine gauge. When my 1 oz bottle of OTO ran out, instead of throwing out the dispenser squeeze bottle, I poured an ounce of this solution in a shot glass and sucked it up into the little old plastic squeeze bottle. And now I am dispensing 3 little drops of OTO to measure chlorine exactly as before.