Core Features: Yealink Acoustic Shield Technology Optima Audio ExperienceTouch Screen LCD: 4.0 inch 480 x 800 capacitive touch screen Multiple Devices Connection Speakerphone Mode Crystal speakerphone Builtin USB Hub: 2ports USB 3.0 hubQi Wireless Charger / Wireless mobile phone charger Customizable Busy light / Supports busyligh tTeams Certified