VOX amPhones BASS - Headphone Amplifier for Bass Directly plugs into your bass Ideal for personal practice Battery-powered (uses 2 AAA alkaline batteries) Built-in effects (compressor) The headphone section uses reliable audio-technica closed-air dynamic headphones, allowing for natural bass sound reproduction. I think it's the perfect headphones for practicing at night, but I'm not a fan of headphones to begin with, so I only used them once for a sound check after purchase, making them a near-mint item. The batteries that came with the purchase are still installed. I confirmed that the power lamp lights up when the switch is turned ON, and each control functions normally. If the batteries are dead upon arrival, please replace them yourself before use. No original box. Shipping will be on days other than Tuesdays and Thursdays.