Battery type: Li-polymer Capacity: 270 mAh Voltage: 3.7 V Energy: 1 Wh Dimensions (L x W x H): 3.9 x 3.2 x 0.7 cm Number of cells: 1 Weight: 9 g Compatible with the following device models: Sennheiser PX 310 BT Sennheiser MM 550-X Travel Sennheiser PX 210 BT Sennheiser MM 550 Travel To ensure compatibility, please check to see whether the battery you are currently using is listed below.
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