These blue Optima Microfibre General Purpose Cloths are manufactured using microfibre split fibre technology. This ultra fine fibre density lifts dirt, moisture, trapping and removing bacteria. Excellent absorbency and dirt removing capacity. Cleans away dirt and moisture quickly and easily with little or no chemicals or detergents. All cloths are colour-coded to avoid cross contamination. Each cloth is washable at 90°C over 500 times.