semi-flex discsUnlike most semi-flex discs equipped with a technical fibre backing and center, our semi-flex discs are pure fiberglass, making for a more durable, longer-lasting, more aggressive-cutting disc, with no need for a back-up pad.  Just right for fiberglass, concrete, stone, and marble.  Available in Silicon Carbide, these semi-flex discs can easily outlast standard resin fibre discs, making it very cost effective.