Lisko-S polishing discs are intended for use in smoothing and finishing thermoformed appliances. Lisko-S discs (blue) are specifically intended for final polishing. These discs feature a half-open stabilized structure that lasts at least four times longer than standard Lisko discs. Use at 4,000 – 10,000 rpm, with a light application of pressure. Always wear protective eyewear during use. These standalone replacement discs are identical to those that are included with the Erkodent Trimming and Polishing Kit.