The BBC Model A was created as a lower-cost variant to encourage higher sales outside of the schools sector. It was launched at a price of GBP£235 (compared with GBP£335 for the Model B). This price rose to GBP£299 as Acorn found they couldn't make it at the lower price.
While physically identical, the Model A lacked a number of internal components and interfaces.
16Kb RAM instead of 32Kb (although the empty sockets were present on the motherboard The Model A lacked a 6522 VIA chip (again with an empty socket on the board) None of the expansion ports on the underside of the machine were fitted.