K-resin Drosophila vials are precision moulded from pure, virtually unbreakable K-resin plastic. These narrow fly vials are bulk packed as 500 vials per case oriented in the same direction for easy transfer into vial trays. K-resin culture vials are perfect for shipping flies due to the strength and scratch-resistant qualities of the plastic. The straight walled shell vial design makes for easy plugging and racking providing the ultimate efficiency for your lab.