Battery type: Li-polymer Capacity: 600 mAh Voltage: 3.7 V Energy: 2.2 Wh Dimensions (L x W x H): 4 x 2.4 x 0.5 cm Number of cells: 1 Weight: 10 g Compatible with the following device models: Sennheiser HD 4.40 BT Sennheiser HD 4.50 BTNC Sennheiser Urbanite XL To ensure compatibility, please check to see whether the battery you are currently using is listed below.
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