... by the needle-hub's color for the clear recognition; 1)Delicately-designed needle-point with features of sharpness,smooth puncture ... reflux; 3)Available size Available lenth:1/6",1/4",1/3",1/2",5/8",3/4",1",1.25",1.5",2". size diameter mm ... green 0.90 20G yellow 1.10 19G cream 1.20 18G pink 1.60 16G white 1.80 15G blue-grey2.10 14G pale ...