All of these drill bits are different in size except for the 90 and .22mm which are both 0.0087 inches in diameter, the 85 and the .28mm which are both 0.0110 inches in diameter, the 13 and the 4.7mm which are both 0.1850 inches in diameter, the 4.8mm and the 12 which are both 0.1890 inches in diameter, and the 1/4 inch and letter E bits which are both 0.250 inches in diameter.