The original launch of the ValveKing series back in 2005 caused quite a stir, with cool boutique-inspired features and a keen price point. The ValveKing series is designed in the US, but built in China hence the low prices. Featuring patented features such as Vari-Class, USB out, Mic Simulated DI out, and the T.S.I circuit you get a lot of bang for your buck.
Vari-Class control adjusts the amp's response characteristics from modern Class A/B push-pull to vintage Class A, or ANY tone between the two. T.S.I stands for Tube Status Indication giving you a constant update of the status of your tubes.
More info at Peavey.com