Used Original Vox headphone amp.

The first-generation Vox amPlug 1 Classic Rock headphone amplifier is a compact, palm-sized practice tool designed to deliver the high-gain roar of a vintage UK-made 100-watt valve amp stack directly to your headphones. Released between 2007 and 2014, the original V1 model utilizes a 100% analog circuit with four gain stages to faithfully mimic the vacuum tube response and harmonic overdrive of a cranked classic rock amp.

Hardware & Controls

• Top Dials: Features three small rotary wheels for Gain, Tone, and Volume.
• Input Plug: Equipped with a fixed, rigid 1/4" (6.35mm) jack sticking out from the bottom to plug straight into your guitar.
• Side Audio Jacks: Features one 3.5mm stereo headphone output and one 3.5mm AUX input for jamming along to external audio.
• Power Controls: Features a simple slide-style On/Off switch accompanied by a red power LED
• 
  Specs
• Power Source: Operates on two AAA batteries.
• Battery Life: Provides up to 15 hours of continuous play with alkaline batteries, or roughly 9 hours with zinc-carbon batteries.
• Weight: Extremely lightweight at 40 grams(1.41 oz) without batteries.
• Dimensions: Measures 86 mm x 80 mm x 31 mm(3.39" x 3.15" x 1.22").