Know Your Needles A Quick Nursing Guide! , Today, lets understand the different types of needles and their clinical purposes , Green Needle (21G) For IM injections like vaccines or How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust Dr. prescribed B12 injections. Pharmacy only gave me vials. Where do you get your needles and syringes? What size?? Where do I inject? : r B12_Deficiency Sandoz Vitamin B12 Injectable Solution 1000 mcg 10 mL Vitamin B12 Sizes of Insulin Syringe Amazon.com: Ulove Prs 12 Pack 1ml Industrial Syringes with 25Ga 1 Inch Needle, Plastic Disposable Syringe and needle for Scientific Labs, Liquids Refilling and Measuring : Industrial & Scientific