The BD Ultra-Fine III Mini pen needle is 31 gauge, 5 mm (3/16"). It's the shortest pen needle in the world, and no pen needle is thinner. It can be safely used by both children and adults, providing reliable injections with no "pinch-up" of skin required. You should consult with a health care professional before switching to a shorter pen needle.

Today's insulin needle is thinner and more delicate for greater comfort, so needle reuse can damage the tip and cause injury. May be used as replacement needles for all Type A insulin pen delivery devices including: