This sophisticated two line business phone provides 50dB amplification. This ST250 business phone digitally adjusts frequency-specific volumes so that any user, especially those in noisy environments, can comfortably hear a caller's voice. The conference grade speaker phone restores low-frequencies sounds to deliver a crisp acoustic experience only found in high end phones. Huge 7.4", 3 line display is easy to read, even from a distance. Phone also includes a visual caller ID, conference-grade amplified speakerphone, RJ22 and 2.5mm headset jacks with built in amplification, a 99 name directory, 7 one-touch memory dials, and one touch call forwarding.