The Definity 8400 Series voice terminals work in both 4-wire and 2-wire DCP configurations. There are ten different types of 8400-Series voice terminals: the 8403, 8405B, 8405B Plus, 8405D, and 8405D Plus, 8410B and 8410D, 8411B and 8411D, and 8434DX.

The Definity 8500 Series voice and data terminals are used with the Integrated Services Digital Network (ISDN) communication system through a 4-wire "T"-interface. Models included ISDN 8503T, ISDN 8510T, ISDN 8520T and ISDN 8528T. The ISDN 8500 Series voice and data terminals can be used with the Definity Communications System Generic 2 and Generic 3, and the Definity ECS.

Definity 8400/8500 Series Digital and ISDN Phones

Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8403 Digital Phone (3233-03B)

Definity 8403 Phone (107702144) The Definity 8403 Telephone features conference, transfer, drop, and hold built-in for your convenience. Features 3 call appearance/feature buttons Group listening...

Definity 8403 Phone (107702144) The Definity 8403 Telephone features conference, transfer, drop, ...

In Stock
$25.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8405B Digital Phone (3233-5B)

Definity 8405B Basic VoiceTerminal 3233-5B (Non-Display) The Definity 8405B Basic is a non-display phone with call appearance/feature buttons. Features 5 call appearance/feature buttons 1-Way Speakerphone...

Definity 8405B Basic VoiceTerminal 3233-5B (Non-Display) The Definity 8405B Basic is a non-displa...

In Stock
$29.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8405B+ Digital Phone (3233-5SB)

Definity 8405B Plus Voice Terminal 3233-5SB (Non-Display) The Definity 8405B Plus Voice feature conference, transfer, drop and hold built-in for your convenience. Features 5 call...

Definity 8405B Plus Voice Terminal 3233-5SB (Non-Display) The Definity 8405B Plus Voice feature c...

In Stock
$35.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8405D Digital Phone (3233-6B)

Definity 8405D Basic Voice Terminal 3233-5SB (Display) The Definity 8405D Basic features a 2-line, 24-character liquid crystal display (LCD) with a one-way speakerphone. Features 2-Line...

Definity 8405D Basic Voice Terminal 3233-5SB (Display) The Definity 8405D Basic features a 2-line...

In Stock
$31.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8405D+ Digital Phone (3233-6SB)

Definity 8405D Plus Voice Terminal with Display 3233-6S The Definity 8405D Plus Voice features a 2-line, 24 character LCD with a two-way speakerphone. Features 2-Line,...

Definity 8405D Plus Voice Terminal with Display 3233-6S The Definity 8405D Plus Voice features a ...

In Stock
$49.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8410B Digital Phone (3234-04B)

Definity 8410B Voice Terminal w/o Display (3234-04B) The Definity 8410B Voice features call/feature buttons and a programmable speakerphone. Features Definity 8410-B Voice Terminal without display....

Definity 8410B Voice Terminal w/o Display (3234-04B) The Definity 8410B Voice features call/featu...

In Stock
$45.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8410D Digital Phone (3234-05B)

Definity 8410D Phone Set 107702870 (Display) The Definity 8410D Phone features a 24 character display, call/appearance buttons and softkeys. Features 10 call appearance/feature buttons 2-line...

Definity 8410D Phone Set 107702870 (Display) The Definity 8410D Phone features a 24 character dis...

In Stock
$33.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8411D Digital Phone (3235-TRB)

Definity 8411D Telephone with Display The Definity 8411D Telephone is passageway ready with a LCD display and programmable speakerphone. Features 2-line, 24 character display. 4...

Definity 8411D Telephone with Display The Definity 8411D Telephone is passageway ready with a LCD...

In Stock
$44.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8434DX Digital Phone w/ Power Supply (3236-06B)

Definity 8434DX Telephone with Power The Definity 8434DX provides users with power and 34 call appearance/feature buttons. Features 34 call appearance/feature buttons. 2-line, 40 character...

Definity 8434DX Telephone with Power The Definity 8434DX provides users with power and 34 call ap...

In Stock
$99.88
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8434DX Digital Phone w/o Power Supply (3236-06B)

Definity 8434DX Telephone without Power The Definity 8434DX provides users with five soft keys so that they can activate 15 different functions. Features 34 call...

Definity 8434DX Telephone without Power The Definity 8434DX provides users with five soft keys so...

In Stock
$71.88
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8510T ISDN BRI Phone (3117-001)

Definity 8510T ISDN BRI Voice Terminal (107538464) Lucent Technologies’ ISDN 8510T Terminal gives you the best of all worlds: rich voice features, extensive data capabilities,...

Definity 8510T ISDN BRI Voice Terminal (107538464) Lucent Technologies’ ISDN 8510T Terminal gives...

In Stock
$54.99
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity 8520T ISDN BRI Phone (3116-001)

Definity 8520T ISDN BRI Voice Terminal (3116-001) The Avaya 8520T ISDN BRI (Basis Rate Interface) Voice Terminal is an all around, multi-purpose, mid-range product intended...

Definity 8520T ISDN BRI Voice Terminal (3116-001) The Avaya 8520T ISDN BRI (Basis Rate Interface)...

In Stock
$189.00
Definity 8400/8500 Series Digital and ISDN Phones
Avaya Definity ZE801A Expansion Module (32300)

Definity ZE801A Expansion Module Features Contains 24 LED buttons The first 18 LED buttons may be administered as call appearances or features The remaining 5...

Definity ZE801A Expansion Module Features Contains 24 LED buttons The first 18 LED buttons may b...

In Stock
$135.00