Yealink SIP-T54W IP Phone features an adjustable 4.3-inch color LCD screen that you can readily adjust it to the comfortable viewing angle according to yourself. As to the audio quality, the SIP-T54W is coupled with the latest version of Yealink Optimal HD Voice technologies, including Yealink Acoustic Shield technology, that effectively eliminate background distractions and noises, deliver crystal clear voice even in a noisy environment. Meanwhile, complying with the latest Hearing Aid Compatibility (HAC) Regulations, its HAC handset helps the person who is with hearing loss to hear the voice more clearly.