Sunfire Signature... what is this?

Recently bought a Sunfire Signature amp, believing I was getting the 600x2 model. The front panel has "Sunfire" above the Joules meter, and "Load Invariant High Fidelity Stereo Power Amplifier" below. A Bob Carver signature is on the upper left of the panel. The rear panel has "Sunfire Signature" just above the serial number (which starts with 99), and a lot of the other normal printing. The two speaker fuses are labeled "5 Amp SLO-BLO MDL/Q", and the AC line fuse is labeled "10 AMP MDA-10 120 VAC", which makes me question if this is a Sig-600. Any thoughts?