HCCS Econet Module (top)
HCCS Econet Module (bottom)
The HCCS Econet Network Board Issue 4 is dated 1991 which implies that the board was intended for Acorn 32bit computers rather than the BBC Master. The components are on the underside of the board and the legs are short which would enable the board to be fitted underneath a mini-podule on an A3000. It probably works in a BBC Master as well.
The HCCS Econet Module uses the ST Microelectronics EF68B54 Advanced Data Link Controller.