This poly brush fits directly onto the bottom of our 20 inch heavy duty floor buffer. It is great for scrubbing light soils on waxed or finished floors. The brush is manufactured to exacting performance specifications for durability and peak performance. Polypropylene bristles are actually slightly stiffer nylon, but are a more economical option, because they will not last as long as nylon. Take a look at our complete line of rotary scrub brushes and rotary floor scrubbing buffers for other options.