The Unitree A1 is a small-to-medium quadruped robot with a maximum continuous running speed of 3.3 m/s (11.88 km/h), described as the fastest and most stable in its class in China. It carries a 5 kg effective load for 1 to 2.5 hours. Joint motors deliver 33.5 N·m maximum torque at 21 rad/s with industrial-grade cross roller bearings, supporting quick removal. Four foot-end pressure sensors provide real-time contact state perception with hardware force sensors and motor current sensing integrated. The Standard version includes an intelligent depth camera with active infrared stereo technology from 0.3 to 10 m at 1080p resolution, real-time HD video transmission, and secondary development with upper and lower-level real-time APIs. The Exploration version adds LiDAR for dynamic obstacle avoidance, map construction, navigation planning, and autonomous positioning, plus a super hash rate AI module for skeleton recognition, gesture recognition, and vision professional secondary development. Optional modules include 6-array microphone voice intercom, ultra-wide range camera, and ultrasound. Rich external interfaces include 2 HDMI, 2 Ethernet, and 4 USB ports with 24 V external power input and 5 V, 12 V, 19 V outputs. A single A1 demonstrated over 80 consecutive backflips at CES 2020. Targets household and entertainment.