Sony WF-1000XM4 Charger Case Replacement Battery 520mAh 3.85V (YY2948)

Bring your Sony WF-1000XM4 charging case back to life with this new replacement battery, designed specifically for the charger case model YY2948.

If your case no longer holds a charge, drains quickly, or won’t fully charge your earbuds, this 520mAh Li-ion battery is the reliable fix.

🔋 Battery Specifications

• Battery Model: 702428
• Capacity: 520mAh
• Voltage: 3.85V
• Type: Li-ion
• Condition: New
• Compatibility: Sony WF-1000XM4 Charging Case (Model YY2948)

⚠️ Important

• Fits the charging case only (not the earbuds)
• Confirm your case model is YY2948 before ordering
• Professional installation recommended