Gauge Colour O.D. Regular Needle Length 28G Blue-green 0.36mm 13mm(1/2") 27G grey 0.40mm 13mm(1/2") 26G brown 0.45mm 16mm(5/8") 25G orange 0.50mm 16mm(5/8") 24G purple 0.55mm 19mm(3/4") 23G blue 0.60mm 25mm(1") 22G black 0.70mm 32mm(1 1/4") 21G green 0.80mm 38mm(1 1/2") 20G yellow 0.90mm 38mm(1 1/2") 19G beige 1.00mm 38mm(1 1/2") 18G pink 1.20mm 38mm(1 1/2") 16G white 1.60mm 38mm(1 1/2")