Yes, the dark grey heat sink models with the black and red logo in the middle. i have a usa4050 right now bridged on my alumapro components, still passive. have a usa4080 on the way, going to bridge the 4050 to a pair of creative sdx7 8 ohm mids and use the 4080 for dayton reference mids/tweets in the a-pillars. that 4050 gets pretty damned hot to the touch bridged on my components, is this normal? thinking about picking up a second 4080 so it will maybe run more efficient and cooler. i LOVE the sound of it. with my crossfire vr602 i always had a little bit of feedback, really low hissing i could hear with the deck turned all the way down. its dead silent now, no ground change or anything, just swapped amps. Some have been known to get a little hot, so no big deal. Mine did get hot after long drives and hard use. I keep my eyes out for them from time to time on ebay. Seem to always get out bid at the last minute. Was able to snatch up a 6 channel cousin in the mean time. IMHO the zed US Acoustics are pretty damn good. Nice and clean and do rated power if not a little more. I run a 4050 and 2 2150s. The only reason Im changing is power and space.
