<p>A relatively large bore (generally gauge 16) needle is inserted into the medial antecubital vein of the arm.  A large needle is needed to prevent hemolysis of the blood cells.
</p>
This photo was taken by myself (camera phone) of my right arm at an Australian Red Cross blood bank (Sydney), and is free for use/distribution.
<a href="https://en.wikipedia.org/wiki/User:Waldszenen" class="extiw" title="wikipedia:User:Waldszenen">Waldszenen</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>
12 July 2006 (original upload date)
Transferred from <span class="plainlinks"><a class="external text" href="https://en.wikipedia.org">en.wikipedia</a></span> to Commons.