P-graded aluminum oxide is tough and offers a very consistent scratch pattern for a high-quality finish Open-coat construction for more flexibility and clog resistance than a closed-coat disc Paper backing for flexibility, and can be used wet or dry Hook and loop fastener for ease of use and quick disc changes Used with a molded rubber or foam backing pad (sold separately) Premium heat-treated grain provides 30-50% faster cut rate and extended life Premium B-weight latex fiber re-enforced paper backing is tear resistant, more flexible and provides easier disc removal FEPA P-graded grain achieves a more consistent, uniform scratch pattern No system anywhere holds better or fastens more easily than Speed-Grip The quick-change hook and loop fastening system locks and unlocks each and every time, providing cooler cutting action and a finer finish