The P4-D from Guozi Robotics is a double-depth autonomous tote-picking robot with QR code and laser reflector navigation, accessing 1 to 8 mast layers with docking heights from 310 to 4945 mm. It has a 300 kg maximum payload, measures 1739 by 880 by 5275 mm with a 1910 mm rotating diameter, and handles bins from 300 to 610 mm long by 340 to 400 mm wide for double-depth rack access. It operates at up to 1.2 m/s with over 8 hours runtime and under 1 hour charging.