Black Bluetooth Neckband Earphones Features Model: KSC-833 Battery capacity: 90mA (with protection board) Playtime: 5 hours Standby time: Power off state > 2 months Bluetooth version: V5.0 Chip: Jerry 6956A Shell material: silicone Speaker specification: 10mm Speaker impedance: 32ohm Frequency range: 20-20KHz Sensitivity: 98±3DB Transmission distance: 12m Product weight: 27.6 Dimensions: 190*125*15 Material: silicone + metal aluminum ear shells