Compatibility: This z-axis device is suitable for -5.5S, TTS-25, TTS-55, TTS-10 laser-engraver without modifying the device. Will not fit other brand engraver without adapters or mod. Focusing is More Convenient: Just turn the knob to adjust the height of the z-axis laser-module. It made adjustment of laser-so much easier. It can remove all excess play between the laser-and the project. Quality : This device is designed and constructed, very solid and the action is smooth, without backlash, very precise, it makes precise laser-adjustment very easy. Adjustment Stroke: The maximum lifting stroke is 55mm, which enables the laser-to engrave thicker items, such as skateboards, wood etc. Lightweight, 0.32 pounds (146g), does not affect the speed and accuracy of the XY axis of the engraver. More Possible: If you want to another brand of laser-engraver, you can modify the hole position or design the adapter and build the adapter with a 3D printer. Colour: Black material: metal Package Contents: 1pcs engraving Only the above package content, other products are not included. Note: Light reflection and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.