The Andrew-AW is an externally mounted PTFE cartridge seal for highly corrosive products. Its special cartridge design allows for easy installation by sliding it along the axis, securing it to the stuffing box, and removing the clips (with a fixed working length). Once completed, the seal is ready for operation.

Its design features hydraulically auto-balanced faces, which diminish heat during operation. Although the AW's wetted parts are made of metal, they can be economically manufactured in corrosion-resistant alloys.