The micro vial insert can be used with screw vials, crimp vials or snap vials. There are usually three types of Micro-insert s produced by Aijiren, 250uL Micro-insert with mandrel interior&polymer feet, the specification is 29*5.7mm, 250uL Conical Micro-insert, the specification is 31*5.7mm, 300uL Micro-insert, the specification is 31*6mm.