Features: High Definition Voice Tips. Call FSK/ DTMF Automatic Identification and Decoding. 99 groups of 12/15 incoming calls, 46 groups of 12-bit deelectrification, or 18 groups of 16-bit deelectrification. 10 groups of 16-bit double-bond memory. 3 groups of 32-bit single-bond memory. LCD brightness 16-level adjustable. Flash time: 300MS/ 100MS/ 600MS (default)/ 1000MS. Exit codes (0-9), long distance codes and local codes can be set. It has the function of pre-dialing number, new call sign and repeat call sign. Call number, call number, delete, call back. Check incoming calls, outgoing calls, phone books or pre-dialing numbers, pick up the phone and dial out automatically. External ringtones and built-in ringtones selection function. Provide RJ-11 interface with 2.5mm headphone jack (for training or recording interface). Innovative tone balance technology to restore voice clearly. Broadband high-definition speaker, optimize the sound of voice and audio segment, fully display the perfect sound quality of human voice. Professional microphone noise reduction technology, can screen 99% background noise. International standards for hearing protection, effectively prevent sudden high decibel sound damage to the ear. Slow rebound stainless steel bar, adjustable length, suitable for different head type wear. Super soft and slow rebound earmuff, comfortable to wear, suitable for long-time wear. Specification: Item Type: Bluetooth Speaker Material: ABS Optional Style: BN220+A16-RJ, BN220+A26-RJ Call Box Battery: 2 * AAA 1.5V Battery (Not Included) Headset:  Noise reduction function: dual noise reduction technology Microphone: single-directional noise reduction microphone Interface: RJ11 Crystal Head Impedance of Impedance: 2.2K/Ω Mills sensitivity: -38dB±3dB Wire control function: 100-4800HZ Speaker Impedance: 150Ω Speaker sensitivity: 116dB±3dB Size: Approx. 14.2 * 9 * 5.5cm / 5.6 * 3.5 * 2.2inch Weight: Approx. 436g Package List: 1 * Call Box 1 * Headset 1 * Cable 1 * Bracket 1 * User Manual Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-DIMEANI official store