AquaChek 541604A Select 7-in-1 Test Strip Kit - 6 Pack

Directions in English. 

Just dip an AquaChek Select test strip in your pool or spa water for one second and remove it immediately. You get results in seconds! It's a simple, cost-effective way to ensure that the water is safe. 

The Select Kit includes: 

To keep your pool at its best, test at each end at least twice a week, and test your spa before each use. You may also want to write down your results so you can track changes over time.