The Avaya 4406D+ Digital phone has 6 programmable feature buttons. It displays caller information for incoming calls--the name and/or number of external callers as well as the extension and co-worker name for internal calls that you receive.

The Avaya 4412D digital phone has 12 programmable feauture buttons. This phone is designed to provide the most common phone functions required to achieve maximum employee productivity and overall value.

The Avaya 4424D+ telephone is a good management phone with 24 programmable feature buttons and a 2-line by 24-character display.

The Avaya DSS 4450 works in association with the 4412D+ and 4424D+ telephones, each of which can support up to two DSS4450 adjuncts. Auxiliary power is required. Each DSS4450 provides an additional 60 programmable call appearance/feature keys with twin lamps.