You are looking on a BRAND NEW OEM Sennheiser MX500 Earphone...
"...The definitive upgrade or replacement earphone for all portable Cassette, CD, MP3/MP4 players, and DVD players.A headphone upgrade is generally the single biggest improvement anyone can make to a portable - as most players ship with relatively mediocre earphones..."Features & Specifications:

• Ultra-lightweight - comfortable fit
• Tiny volume control on lead
• Crystal clear sound with powerful bass
• Sound pressure level (SPL): 125 dB
• Frequency Response: 18Hz to 22kHz
• Nominal impedance: 32 Ohm
• Color cool metallic blue