1. Delicate and compact, easy to carry,laser-engraving process, never fade 2. Personalized DIY function, tube plug-in type, can be upgraded Op amp plug-in type, 3. Powerful thrust can be pushed up to 600 Euros, 32-300 Euros is recommended. The best effect HD650 / 600, DT880 / 770 / K701 / 702Q701, etc. 4. A wide range of applications, clever acoustic structure design, so that the sound effect is full and clear, the bass is powerful, effectively restore the real sound, and bring you a more perfect tory feast 5. Suitable for players / MP3, mobile phones, desktop computers, tablets, notebooks, game consoles colour:black Material:Aluminum alloy size:11*7.3*3.2CM Package Contents: 1* headphone amplifier 1* power adapter 1* recording cable Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.