- Cortelco Colleague corded two-line telephone- 90V Message waiting lamp- Handset volume control- Hook delay (positive line disconnect)- A-lead control- Data jack- Hearing aid patible-Hold with LED indicator (flip-flop type)- Last number redial- Flash (100-300-600mS) switchable- 10 One-touch programming memory- Mute with LED indicator (flip-flop type)- Speakerphone with LED indicator- Headset control switch- Line in-use status with LED indicator- Conference button- FrostITT2205FROST