Mitel Superset 4025 Speaker Display Phone (9132-025-200, Dark Grey, Refurbished)Mitel Superset 4025 Speaker Display Phone (9132 025 200) The Mitel Superset 4025 (Part #9132 025 200) is a reliable digital business desk phone designed for Mitel SX communication systems. Featuring a multi line display, programmable feature keys, and speakerphone capability, it is ideal for office professionals and administrative users. The Superset 4025 is commonly used in legacy Mitel environments, including offices that rely on SX series systems