When the Keyboard Component project was canceled, Mattel searched in a
hurry to produce a small and cheap computer.
They contacted Radofin Electronics Far East, based in Honk-Kong,
who was manufacturing most of the Intellivision products.
Radofin had just developped a line of three Z80 based computers.
Mattel decided to sell the two first under their brand.
The Aquarius 1 and 2 were born. 

The Mattel Aquarius uses a special version of the Microsoft Basic.
When it is used with basic, only 1.7 KB are available. 

There were no redefinable characters, but 256 predefined were available :
128 ASCII (numerals, upper and lower case alphabet, punctuation, symbols)
and 128 graphic patterns.
That was the only "graphical" features of the Aquarius ! 

Unfortunately the specifications were so poor for a 1983 computer,
that the Aquarius "1" litteraly bombed. Three months after its release,
Mattel decided to cancel the project and to sell back the rights and
stocks to Radofin. 

Radofin continued to sell Aquarius 1 & 2 under its own name,
but without success... 

Cool addons were developped for the Aquarius, but never made it to the shelves
(apparently). There were a Master Expansion Module equiped with disk-drives
and expansion slots for future addons.
It even offered the CP/M compatibility ! 

Another sympathetic extension was the Home Computer System Command Console
which allowed the Aquarius to directly control up to 255 electric devices.
But when the computers is used with this extension, it can't be used
for anything else ! 

There were also a Modem planned and Mattel even announced network services
for games and programs downloads... 

(www.old-computers.com)