FISCH Wave Cutter Forstner Bits have been seriously engineered. The bits are forged, before being CNC ground and then hardened meaning; accuracy and sharpness are a premium. The unique 'Wave' cutter design has many benefits compared to a more traditional Forstner. The serrated 'Wave' edge generates considerably less heat and allows cutting speeds to be increased with less effort needed to achieve each hole. Metric sizes have 8mm shanks up to 30mm diameter and 10mm shanks there after. All have an overall length of 90mm. Forged from one piece of high quality tool steel for extra strength. Made in Austria. For the best results, use in a pillar drill.