A 300 µL insert is fused into a 12 x 32 mm clear or amber glass vial. 300uL Micro-Insert, 31*6mm,clear glass,flat bottom, for 9mm Vials, 100ea/pkg. Vial Insert, 6mm Clear Glass Insert Conical Base, Volume 250ul . Polyspring glass hplc vial Insert : Polyspring can protect vial's bottom and insert.