Go-Vibe V5 portable amplifier. Good condition, works perfectly, sure to last for years. PayPal $30 total, Priority Mail with delivery confirmation to the USA - good price. Made by Norm, who no longer makes Go-Vibe amps.
I characterize its sound as clear, lively and fun. I enjoyed it most with my JVC RX700 headphones. It is my favorite < $100 portable amp of the few I've owned. I suggest using it with headphones under 100 Ohm regardless efficiency rating.
Selling as I no longer use it. Includes a new battery. Has a power connection on the side that I did not use. I don't have a wallwart A/C adapter for it and don't know what kind is required. You can search GoVibe V5 for more info. I bought this amp used a while back but forget the details.