This compact Boston amp (tested and working properly) puts out 55 watts RMS to each of its four channels, or up to 245 watts RMS by two channels in bridged mode. It can handle low-impedance loads, providing flexibility when putting together a system and allowing maximum power. It features a forced air cooling system, which is more efficient than a traditional amp heat sink. Air cooling allows this amp to be be mounted in any position, even upside down, without fear of failure due to excessive heat. Adjustable mounting feet make it even easier to adapt the GT-40 to uneven surfaces found in some vehicles. Boston's Q-Tune feature gets the best bass response from any type of speaker. Variable frequency filters allow the right signals to be sent to the right places, reducing wear and tear on your speakers. You'll find all controls and connections on one side of the amp, making installation and adjustment as simple as possible. There are some cosmetic marks on the amp. The amp measures 14.25" x 7.75" x 2.25".