NEC Aterm WR8170N-HP

Product page

"48RNRA0K.0GA", "2010/04/07", "Welkin-HP", and "AL1-002484-00"<...> is silkscreened on the top of the board in the images provided by Mns below.
 * The 802.11bgn radio (AR9283) is using two Skyworks (SiGe) SE2598L / 2598L (19dbm) 2.4GHz power amplifier ICs.

Serial port pinout
 J2 (VCC) (GND) (N/A) (TX) (RX) pin5 pin4  pin3  pin2  pin1

Vendor links
On Amazon.co.jp
 * ASIN: B003MZQR16, Date added: 2010-05-19, Shipping weight: 566g