The latest PJB D400 answers the quest for powerful, high fidelity and light weight amplifier all in a beautifully designed package. We also wanted to make it completely noise free; so we use the latest high efficiency class D amplifier designs to eliminate the need for a fan. As a result, this amp is totally quiet, runs cool and therefore extremely reliable. The chassis are precision made from aircraft grade anodized black aluminum. The D400 comes with a padded soft gig bag to preserve their beauty over years of usage. This amps is standard 1U to allow the possibility of being rack mounted.