Elsonic / ELSONIC / Earphones [Built-in Memory / Bluetooth / Ear-hook Type / Bone Conduction / Waterproof / Microphone Compatible] / ECD-BTBCH02 Memory-equipped Wireless Bone Conduction ・Waterproof Rating: IPX7 ・Listen to music without a smartphone ・Supports calls, clear voice ・Memory Capacity: 16GB Wireless Method: Bluetooth Ver. 5.3 Communication Distance: Up to approximately 10m (varies depending on the usage environment) Radio Wave Strength: Class 2 Radio Frequency: 2.4GHz band Built-in Battery: 135mAh 3.7V Lithium Polymer Battery Charging Input: DC5V 130mA Charging Time: Approximately 2 hours Continuous Use Time: Approximately 6 hours (at 60% volume) Standby Time: Approximately 200 hours Supported Codec: SBC Frequency Response: 160～60kHz Microphone Sensitivity: -38dB Waterproof Rating: IPX7 Size: Approximately Width 120mm, Height 132mm, Thickness 47mm Weight: 34g Seems good for listening while working in the office. Regular price: 5980 yen Unopened product Thank you.