Standard opening vials require 5mm inserts, Wide opening vials 6mm Inserts Shop Fisherbrand™ 0.2mL Micro-Insert, Polypropylene, for wide opening vial at Fishersci.co.uk Fisherbrand™ 0.2mL Micro-Insert, Polypropylene, for wide opening vial flat bottom,0,5 mL Volume,<8 µL residual volume,31 mm height Autosampler Vial Inserts | Fisher Scientific