[8881 AA Battery Box] Features an AA battery box that can power 2 XL motors or 4 M motors simultaneously, requires 6 AA batteries (battery not included). [M Motor 8883 for High-speed] The motor delivers strong power. High-speed, low-torque building block motor kit. Supports forward and reverse operation. [2.4G Remote Control & Receiver] The motorized system includes a 4-channel selector on the remote control. Devices must be set to the same channel to operate together. The remote is powered by 3 AAA batteries (battery not included). [Compatibility with Building Blocks] The set is compatible with most standard building block models available on the market. [Safety and Learning] Made from high-quality ABS plastic. Building and assembling blocks helps children develop hand-eye coordination, enhances imagination, and encourages creative play. Material: ABS Plastic Color: Grey Package Contents: 2 x Medium Motors 1 x Battery Box 1 x Infrared Remote Control 1 x Receiver Note: Light and display settings may cause slight color variations between the product and the image. Measurement may vary by +/- 1-3 cm.