Swimming pool water quality tester 1. You all need to prepare a 1.5ppm chlorine solution for your pool water inspection purpose 2. If you are testing for a chlorine level of 1.5ppm or not (unsure whether it is or can't find a calibration point), use a traditional strip 3. Once you calibrate it for you, you don't need to recalibrate again unless you change the measuring pool with a different pool water. A brief description Tester design for swimming pool or spa home scale (excluding salt lake water pool, industrial or use) After a successful calibration, you can test your pool water for chlorine and pH levels a quick and easy way. So no more complicated and confusing "traditional liquid chlorine and acid base kits"! With this practical tester you can quickly test if your chlorine and pH are within the ideal range of 7.8: chlorine 1.2 1.7ppm and pH 7.2 lied. If your test results are out of this range, give you a piece of useful information to adapt the pool accordingly for chlorine and acid-base. This is a great tool you may need to keep your pool water. Specification Recommended chlorine level for swimming pools and spas is 1.2, 1.7ppm Recommended PH pool and spa level is 7.2, 7.8 Size ( CM ) Main body: 190 x 120 mm Probe with handle: 150 mm long Probe (only): 48 mm long (black strap not included in scope of supply) Cable (only): 130 mm long Power: 1 AA 1.5 V alkaline battery Weight: 160 g (without battery) Delivery quantity: 1 set of water quality detector Product color: as pictured *Due to different monitors and lighting effects, the actual color may be slightly different from the picture *Due to manual measurement, please allow 1-3cm deviation