Avaya 700513191 - DECT 3730 Handset This durable handset features enterprise-grade telephony, local phonebook, access to central phonebook, voicemail and more. It has a display size of 1.8 inches, and resolution of 128 x 160 pixels LCD with white LED backlight, which enables operation in complete darkness. The IP DECT 3730 Handset has a duplex loud-speaking function to enable use as a conference phone up to 1.5m from the handset. It includes a 3.5mm jack for connection of headphones and a display illuminated in color. The handset supports 19 languages and features an internal phonebook that stores up to 250 contacts.