This is a Thunderfunk TFB420 bass amp in great working condition. These amps get a lot of love here on TB. They have a reputation for clean, full, warm, and powerful sound, and this one is no exception. Although the amp is labeled as a TFB420, its 50X serial number puts it in the TFB550-A range, according to the Thunderfunk owners manual. It's also marked for a 6.25 amp fuse (as on a TFB550) and is equipped with "The Switch" which wasn't a standard feature on the TFB420. It could be a transition amp, or it may have been upgraded later by Dave Funk. Maybe @Thunderfunk will chime in and give us some more info. This amp sounds fantastic, so it has been used. The outside has a few dings and scuffs, but the inside is absolutely fine. The amp was serviced and given a clean bill of health by Vintage Bliss Amplification here in Middle Tennessee. The amp comes with a used SKB hard case (which will fit the amp without the carry handle installed) and a six-foot power cord. I loved this amp so much, that I went out and bought a Thunderfunk TFB750. I can't justify keeping both, so... Price is shipped CONUS. No international shipping. PayPal or cash only. If you'd like to meet within a one hour drive of Nashville and pay cash, I'll knock off 25 bucks! Fore more information, or to download a copy of the owner's manual, visit the Thunderfunk website. An almost life-sized shot of the front is here. An equally huge shot of the back is here. Note: I've blurred out the serial number in the photos of the rear of the amp, but the characters are perfectly legible in real life.