Sennheiser PX100 Ultra rare folding helmet, new in its NEW hard case never used 
Nominal impedance: 32 Ohms
Jack plug: 3.5mm stereo
Remote
Transducer principle (Headphones): dynamic, closed
Ear coupling: supraaural
Cable length: 1.4 m
Weight (w/o cable): 60 g
Frequency response (headphones): 10 to 21,000 Hz
Sound pressure level (SPL): 115 dB (SPL)
THD, total harmonic distortion: 0.1 percent
Sennheiser PX100 Ultra rare folding helmet, new in its NEW hard case never used  Nominal impedance: 32 Ohms Jack plug: 3.5mm stereo Remote Transducer principle (Headphones): dynamic, closed Ear coupling: supraaural Cable length: 1.4 m Weight (w/o cable): 60 g Frequency response (headphones): 10 to 21,000 Hz Sound pressure level (SPL): 115 dB (SPL) THD, total harmonic distortion: 0.1 percent