It are made from high-quality polypropylene (PP) and are pre-filled with sodium thiosulfate (20 mg/L) to preserve water samples for analysis. These bottles are gamma sterilized and come in a pack of 108, making them ideal for handling, transporting, and storing water samples, especially for chlorine analysis in potable water, swimming pools, and other water sources. The bottles feature clear polypropylene, providing excellent visibility, and they have embossed graduations for easy volume verification. The PE caps with self-sealing locks ensure leak-proof and contamination-free sample handling.