PaliPalintest Photometer DPD No 3 Test Tables available in foil blister packs for extended shelf life. Simple and easy you use. Low turbidity and quick dissolving. Specifically designed for photometer use. Adding one tablet to your sample will produce a pink colouration proportional to the amount of Chlorine present. Storage & Handling - Store in a cool, dry place away from oxidizing and reducing agents, strong acid, alkalis, solvents and organic materials. - Do not mix with other chemicals. - Always wear suitable gloves and eye protection when handling. - Use biocides safely. Always read the label and product information before use.