my us400 is the last one they produced .. its in between the us2000 and the next one down now. it will do over 1200 watts easy 3 powers 3 grounds (old ones had 2 of each and drew 45 less amps) and it does not have a x over. its 23" long and still in the skinny chassis (well skinny for us amps) i used to have ties with us amps, still a great company just didnt like the guy who delt with them in my area