This is a 500-unit limited reprint model of the original open air headphones, the HD414. The pop-colored ear pads and high frequency unique to Sennheiser are characteristic (Mizusaki Ryo)
Maintenance information: 2025.11.23 sound output confirmed
Accessories: none
Main specifications: dynamic open air type impedance 52 ohms playback frequency band 18-21,000 Hz; allowable input: 100 mW; weight: 80 g (cord not included)