Made of cellulose filler/polypropylene sleeve. Super-absorbent cellulose socks soak up more than one gallon for every four feet of oils, coolant, solvents or water, making it a true top performer. Ideal for surrounding spilled fluids or wrapping around leaky machines. Easy and convenient to put into place. Contain spills to keep fluids from spreading into larger areas and becoming slippery hazards. Very flexible to conform around machine bases and offer a snug fit with no seepage. Color-coding helps you visually identify the right sorbent for your needs. Gray signifies universal absorbency.