Examples for

Hypodermic Needles

Hypodermic needles are long thin hollow tubes with a hole in a pointed end. Often, they are used together with a syringe to inject liquid material beneath the skin, such as with insulin syringes and vaccination shots. They can also be used to extract liquid from the body, such as during blood tests.
Hypodermic Needles

Hypodermic needle sizes are specified according to a gauge, which can be compared to other gauges used by wires, drills and meshes.

Look up the specifications of a needle size:

#21 hypodermic needle

Find out the typical use for a needle diameter:

typical uses of a #23 hypodermic needle

Determine the closest equivalent wire gauge:

closest wire gauge to a #27 hypodermic needle
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