The Yealink-SIP-T57W is designed for busy executives and professional. It has adjustable 7-inch multi-point touch screen for the comfortable viewing angle according to the personal and environmental needs for a rich visual presentation and easy navigation with just one-touch. It is coupled with the latest version of Optimal HD Voice technologies, including Acoustic Shield technology, which effectively eliminate background distractions and noises, that delivers crystal clear voice even in a noisy environment. It complies with the latest Hearing Aid Compatibility (HAC) Regulations, this handset helps the person who is with hearing loss to hear the voice more clearly. This phone has built-in USB2.0 port with USB call recording via USB flash drive. Its built-in USB 2.0 port allows for USB recording or a direct wired/wireless USB headset or up to three Yealink EXP50 expansion modules connection. It supports s efficient provisioning and effortless mass deployment with Yealink’s Redirection and Provisioning Service (RPS) and Boot mechanism to help you realize the Zero Touch Provisioning without any complex manual settings.