Medicore Insulin Pens & Accessories Case 534 by Medicore Medical Supply GROUP: Needles & Syringes:Syringe/Needle Combo's:Insulin Standard Item Description: Insulin Pen Needle, 31G x 8mm (5/16"), 100/pk, 12 pk/Case Packaging Desc: Needles Insulin Pen 31Gx8Mm100/Pack 12Pk/Case Country of Origin: Harmonized Tariff Code: Product Description: