[8881 AA Battery Box]The power system featuring with AA battery box which can run 2 xl-motors or 4 m-motors at the same time, requires 6 AA batteries (battery not included). [M Motor 8883 for High-speed] The motor provides strong power. High-speed and small-torque building block motor power supply kit. Support forward and backward. [2.4G Remote Control & Receiver]The motorized system feature 4 channel selector on remotes and control. They need to be set on the same channel to work together.The Remote Control powered by 3 AAA batteries (battery not included). [Adapt to Most Building Block Devices]The whole set can basically adapt to most type of building block Devices in the market. [Safety and Learning for kids]Made of high-quality ABS plastic materials.By assembling building blocks, children can exercise their hand-brain coordination ability, stimulate their imagination, and make them enjoy the joy of doing things. Material:ABS plastic colour:Grey Package Contents: 8 x Medium Motors 4 x Battery Box 4 x Infrared Remote Control 4 x Receiver 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.