Audio-Technica ATH-M70x Professional Monitor Headphones (Open Box) used It features an 8 mm

It features an 8 mm dynamic driver unit paired with a balanced armature driver unit

so hang on to that original part

Proprietary Technologies

These earphones may be new

Impedance:    50 ohm

Audio-Technica ATH-M70x Professional Monitor Headphones (Open Box) used It features an 8 mmThe most advanced in the critically acclaimed M Series line, the Audio Technica ATH M70x Professional Monitor Headphones feature proprietary 45 mm large aperture drivers and are tuned to accurately reproduce extreme low and high frequencies (5 to 40,000 Hz) while maintaining perfect balance. They are ideal for studio mixing and tracking, FOH, DJing, mastering, post production, audio forensics and personal listening. Crafted for lasting durability with