They have a real business look about them, very cool and sorta modern/retro at the same time.
From their website:
The Manley 440 Watt Monoblockwas the predecessor to the Manley 500W. It was built from 1994 to 1996. Features and specs are pretty similar to the current 500W model. This amplifier was also built into a black powder coated steel chassis and that model was called the Studio 440.