Key Information: ‣ Size: 4mm ‣ Uses: BD Microfine Plus Pen Needle offers safe and comfortable insulin injection for patients using insulin pens ‣ Directions: Attach to the insulin pen, inject, and properly dispose of the needle after use ‣ Warnings & Precautions: For single use only. Dispose of needles properly in a sharps container. Keep out of reach of children