Olympia AX amps these are a matched pair with consecutive serial #'s for use with the PBN Audio Master Reference loudspeakers to drive the dual 18" subs, the front covers were special order custom made pieces for PBN Audio for their display booth at the CES show a few years back I believe in 2010. I bought these high end amps direct from Peter Noerbaek as they had only a few hours on them when used at the CES show and when on display. I have put maybe another 45-50 hours of use at most since I bought these amps in 2010. One of the amps was sent back to Peter at PBN Audio for minor repair of broken Bnc connector in 2014, and other than that these amps are flawless and sound awesome these are very loud and are switchable high/low bias class A amps for music reproduction. 20 amp power cord and the pictured Billy Baggs Pro Stands X 2 are included.