Compatible with headphone models: Sennheiser HD 505, HD 550, HD 560S, HD 559, HD 569, HD 579, HD 599, HD 599 SE and HD 620S. It is compatible with the HD 500 series and HD 620S headphones. Easy installation and setup: Connect right into HD 500 series or HD 620S headphones, locking securely into place with a twist - without the need for tools, magnets, or adhesive patches.
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