Siemens SpeedStream 4100

Overview
"3015-002182" and a date code of 0535 is silkscreened
 * on the board of one particular unit.

"SIEMENS SUBSCRIBER NETWORKS", "2004", "034-4240-002",
 * and "(Rev B)" is etched onto the bottom of the board.

Askey is presumed to manufacture this device.

Links of Interest

 * On SpeedGuide.net

Serial Pinouts
J1 (...) (...) (RxD) (TxD) [GND]