Technical specifications: Size: M (medium) Shape: Cylindrical Width: 25mm Length, shaft: 43mm RPM, max. 23500 rpm Optimum rpm from: 5000 rpm to 10000 rpm shank diameter: 6mm outside diameter: 20mm Description:Â Due to their hardness and flexibility, rod felts are used where metric shapes metric shapes have to be met exactly. The ZYA cylindrical shape is mainly used around the circumference. The version with frontal perforation (ST-BO) is particularly suitable for frontal use. Materials that can be machined : Stainless steel Aluminium Bronze Copper Brass Titanium Machining tasks Polishing