Bought this to go in my Camaro, but sold the car before I could install this. It is a JL Audio G4500 amp, 4 channel, 500W. The specs are:

500 Watt Four-Channel Amplifier
Continuous Power @ 14.4 V:
80W x 4 @ 4 ohm per ch.; 125W x 4 @ 2 ohm per ch.
THD at Rated Power:
<1% THD, 20 Hz - 20 kHz
S/N Ratio*:
>104 dB referred to rated power
Frequency Response:
10 Hz - 25 kHz (+0, -1dB)
Damping Factor:
>200 @ 4 ohm / 50 Hz; >100 @ 2 ohm / 50 Hz
Dimensions (L x W x H):
13.80 in. x 9.25 in. x 2.50 in. (350 mm x 235 mm x 63.5 mm)

Asking $125 + shipping.

This amp was checked by J&J Electronics in Selmer, TN and is working correctly.