[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 provides strong power. High-speed, low-torque building block motor power supply kit. Supports forward and reverse operation. [2.4G Remote Control & Receiver] The motorized system features a 4-channel selector on the remote control. Devices must be set to the same channel to operate together. The remote control is powered by 3 AAA batteries (battery not included). [Compatibility with Building Blocks] The set is compatible with most standard building block brands available on the market. [Safety and Learning] Made from high-quality ABS plastic. Building and assembling blocks helps children develop hand-eye coordination, stimulate creativity, and enjoy the satisfaction of creating. 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 image and the actual product. Measurement tolerance: +/- 1-3 cm.