BD Insulin Syringes With BD Ultra-fine Needle 100U 31G 6MM:The latest injection technique recommendations published in Diabetes and Metabolism mentions the following. “Shorter needles are safer and are often better tolerated…Initial therapies should begin with shorter needles. Shorter needles reduce the risk of injecting into the muscle. 4, 5 and 6mm needles may be used by any adult patient including obese ones.”Key benefits:As effective as longer needles.Less intimidating.Reduces the risk of a painful injection in the muscle.Engineered with optimal point geometry for maximum comfort and reliability.Coated with special micro-bonded lubrication for a more comfortable injection.Manufactured with a special surgical grade of stainless steel.Non-toxic, non-pyrogenic.