Insert type, Conical Bottom, Flat Bottom, Mandrel Interior & Polymer Feet. Material, Glass for Insert, Polymer for feet. China Hplc Vial Inserts Manufacturers, Suppliers, Company - aijiren. Welcome to wholesale cheap hplc vial inserts from our factory. 31*5.7mm, Suits for 9mm Vials, 250uL Micro-Insert with Mandrel Interior, & Polymer Feet,