The 25 mm 4 ohm member of the NE family has leading-edge transducer technology packaged in a cutting edge, stylistic design. The tweeters in this family feature finite element analysis designed Neodymium-Iron-Boron magnet (NdFeB) motors, with copper caps for extended frequency response and reduced distortion. The aluminium rear chambers offer extended low frequency performance, while doubling as heat sinking. The butterfly supporting the tweeter diaphragm is made of a high temperature plastic, consistent with the products high temperature performance rating, and features supporting terminals. The dome material in this design is silk, and the design has been optimized for sound quality and clarity. Rounding out the design is an aluminium face plate and plastic grille, which offers protection for the tweeter diaphragm.