PES material (chemically known as Polyethersulfone) is distributed by New Technology Plastics in standard stock shapes for machining and is extruded in sheet and rod. The chemical abbreviation for Polyethersulfone has long been PES. However, current standards such as EN ISO 1043:2011 have started to refer to Polyethersulfone as PESU to make it more identifiable as a member of the sulfone family. Since PESU is not commonly used yet, we still refer to it in the following as PES. The high-performance physical property profile of Polyethersulfone shapes makes them an excellent material choice regardless of which nomenclature is used.