Perkin Elmer flat base micro insert for vials-HPLC Vial Inserts Microsampling (center-draining and fused-insert vials) Insert, 6 mm Diameter, Flat Bottom, 450 µL, Silanized. AR0-4615-52 Round Bottom: PerkinElmer,. 400 μL Flat Bottom Vial Insert, 100/pk - PerkinElmer. Material, Clear Glass. Product Group, Vial Inserts. Quantity, 100.0.