Sennheiser HD 4.50 - iFixit
DC 3.7V 650mAh AHB622540N01 Rechargeable Lithium Battery for Sennheiser Momentum 2.0 HD 4.40 HD 4.50 HD 450 Urbanite XL Wireless Bluetooth Headphones Aerox 9 Aerox 5 Mouse : : Electronics
User manual Sennheiser HD 4.50BTNC (English - 37 pages)
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Sennheiser HD 4.50 Motherboard Replacement - iFixit Repair Guide
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Sennheiser HD 4.50 Motherboard Replacement - iFixit Repair Guide
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