All metal shell: sturdy metal appearance design, fully enclosed internal structure, ensuring stable circuit operation, suitable for studio recording Passive aluminum strip, Better sound, Proficient in high standards and long-distance signal transmission requirements DM1 Solve your troubles +28dB gain Class A transistor amplification circuit bottom noise, Effectively solving the problem of low volume caused by low sensitivity Due to different batches, the appearance, color, and printed words of the product may be different, which does not affect the use. Colour:Black Material:Metal Package Contents: 2 * Amplifier Only the above package content, other products are not included. Note: Light reflection 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.