Dewalt sds max drill bits 340540mm dewalt dt9409 qz this 16 x 340mm drill bit from dewalt has been manufactured to a very high standard courtesy of the 4 cutter x head design for improved user comfort reduced vibration and improved hole quality whether you are a professional tradesman or diy enthusiast the 4 flute spiral increases drilling speed and debris removal with a heavy duty shank for maximum durability dewalt dt9409 qz sds max drill bit 16 x 340mm