New, boxed Farallon EtherMac 30i-TN10Mb EtherNet Card for the Macintosh IIsi and SE/30 with 10base2 (thinnet) and AUI connections. The card also features a socket to add a 68882 floating point unit (FPU) to speed up maths calculations. Requires Macintosh System 6.0.5 or later. Known to work with Mac OS 9.x, 8.x, 7.6.1, 7.5.5.
Note that thin ethernet networks require termination with a 50ohm BNC terminator at each end of the chain (unless the last node is an Apple AAUI transceiver which self terminates).