It was not an exact clone as it had a modified ZX81 ROM, however it could be fitted with a ZX81 compatible ROM. It came with 2K RAM (expandable to 16 or 32 K), and a sound and joystick port.
It was not an exact clone as the original ROM was new, but it could be fitted with a ZX81 ROM and become compatible. Comes with 2K RAM (expandable to 16 or 32 K), sound and joystick port.