The hardware specifications of the M2105, observed from manufactured units, include the 6502 CPU (SY6502 or R6502), ULA and 32 KB of dynamic RAM fitted in the Electron main unit, plus 32 KB of static RAM, two 6522 VIA devices for interfacing, AM2910PC modem, SCN2681A UART, and TMS5220 plus TMS6100 for speech synthesis. The speech synthesis was used for the "voice response" function which answered incoming voice calls by playing a synthesised message to the caller. The components chosen and the capabilities provided (excluding speech synthesis) are broadly similar to those featured by the Acorn Communicator which was another product of Acorn's custom systems division.