The IBM 8750 Business Communications System was a voice and data switching system PABX, suitable for medium to large numbers of extensions, used on customer premises.
"[1] The 8750 was the European version of the IBM 9751,[2] also a ROLM design.
In 1984, IBM bought the American company ROLM.
The 8750 had from 91 to 3000 telephone extensions; up to 1000 simultaneous conversations; a computer based on a Motorola 68020; up to 16 IBM 8755 Operator Consoles; a 30MB fixed disk; main/satellite working with IBM 3750 and 1750 Switching Systems; digital trunks in Belgium, Italy and the UK; and ISDN and Systems Network Architecture (SNA) networks.
[3] IBM later sold ROLM to Siemens[4][5] who then continued to market the 8750.