Features: P2 Portable Headphone Amplifier delivers studio grade stereo clarities in a compact metal body, enhancing any headphones performances with sound reproduction and portable design. Crafted from aluminum, this amplifier features universally compatibility with 3.5mm stereo devices and operates on 1.5v batteries (not included) for power in any environment. Ideal for audiophiles and mobile professional seeking enhanced stereo detail during commutes, studio, or extended listening periods. Perfect for critical listening scenarios including travel entertainment systems, home studio monitoring, and outdoor adventures where premium sound quality matter. The metal construction ensures lasting durability while advanced circuitry eliminates distortion, revealing subtle musical nuances often losts in standard playback systems. Specifications: Component: Metal Size:Approx.130mm/5.12''x31.5mm/1.24''x27mm/1.04'' Output: 3.5mm output Power supply methods: 2pcs1.5V batteries (not included) Package Includes: 1Piece In-Ear Amplifier note: Please allow 1mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color of the item.