Before TCP/IP became the all-dominant communications protocol, individual hardware makers such as IBM had their own proprietary communications protocols and devices.
IBM provided customers with various tools to write telecommunications aware software, one of these being BATS II. This manual is intended to help the IBM Customer Engineer assist the customer with the debugging and implementation of that software. The handbook looks British as it has an inscription on the cover to G. Bains in L’Pool (Liverpool?). Good condition but no binder. 7" X 3" X 0.3"