Southwestern Bell MC60 Micro Cassette for Dictation Recorders and Answering Machines Fits all caption drive micro cassette recording devices, phone answering machines, and micro cassette dictation recorders that accept the MC60 small tape format. This tape will record 60 minutes (30 minutes per side) of audio at 2.4 cm/sec or 120 minutes (60 minutes per side) at 1.2 cm/sec if the recorder has adjustable speed.