Abstract: A flashback plug has a body molded of a semi-transparent polymeric material along and about an axis. A distal end of the body engages in fluid tight communication a needle hub flash chamber and a proximal end extends therefrom to receive a fitting. A passage extends through the body along the axis from the proximal end to the distal end to permit flow therethrough. A vent membrane of a hydrophobic filter media is mounted by its periphery across the passage. The vent membrane is insert molded within the body to capture the proximally extending periphery thereof so that liquid in the passage distal end can not reach the proximal end. The proximal end of the passage has the shape of a female luer taper which terminates distally at the vent membrane. A pair of opposed channels extend longitudinally and parallel to the axis from the vent membranes to the proximal end. The distal end of the body has an outside a male luer for engaging the needle hub flash chamber.