-The gauge of the needle is inversely related to the size

of the needle

- 21 gauge: standard for venipuncture

- 23 gauge: for children; 23 or 25 gauge is for winged

infusion set (butterfly)

- 23 gauge butterfly: for small and difficult veins

-25 gauge: collection from scalp or other tiny veins of

infants

Needle length: 1 – 1.5 in: 21-23 gauge

½ to ¾ in: butterfly needle