This is a four-free metal robotic arm, using the mg996 large steering gear, which is powerful. The robot arm has claws that can grab something. Each servo can move 180 degrees, the movement angle is relatively large. The internationally-used for is used as the control board, and our uniquely designed potentiometer knob control board is used to control the four servos. The threshold is very low. About assembly This product does not require welding, no additional equipment, no additional tools, we provide a complete graphic tutorial for everyone to use as a guide. mg996 steering gear, relatively large power For control, universal Four knob control, low threshold for use Distribution power adapter Assembling: We provide online and Chinese-language assembly tutorials and videos in Chinese and English, and are constantly updated and maintained Power supply: Use the 5V2A adapter provided by us, or use the USB-to-DC conversion cable provided by us to use our own power bank. Charging treasure requires a minimum 2A current output. Program: the program has been burned at the factory, and the program source code is provided for download Welding: We have a welding part in our tutorial, Maximum extension length of the robotic arm: 23cm Maximum opening size of clip: 7.5cm Colour:black Material:Metal Size:14.5X9.5X14CM Package Contents: 1 x Robotic Arm Kit 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.