Precision ground bit for fast clean drilling in all types of wood. Threaded tip for self centring self feeding. Smooth flute geometry enables fast drilling and fast chip removal without jamming. One main spur and one pre-cutting spur for accuracy. Suitable for drilling construction timber, hard and soft wood, laminated chipboard and veneerd wood. This set contains 13, 16, 18, 20, 25 x 230mm bits.