Features: Experience the revolutionary 4.2inch electronic label with passive technology, eliminating batteries and maintenance for effortlessly app updates in seconds. Featuring a high resolution 400×300 E paper display in a lightweight ABS case, this electronic shelf label offering sharped visuals, low power consumption, and waterproof durability. Ideal for retailers, supermarket managers, and warehouse professional seeking efficient inventory tracking with smart labeling solution. Perfect for real time pricing and promotional displays in stores, warehouses, and industrial environments, ensuring accurate information with minimal errors. Enjoy friendly, long lasting performances with up to 1000 updates and a 5 year life, reducing waste and operational costs sustainably. Specifications: Type: Electronic paper shelf label Component: plastic Color: black/red (optional) Size: as shown in the picture Screen size: 4.2 inches Screen resolution: 400x300 Refreshing power: ≤20mW Picture updates time: 3s (black and white)/16s (black, white and red) Updates picture: updates picture Language: Default English Overall dimensions: 104.8x94x10.18mm Field of view size: 84.8x63.6mm Working temperature: 0℃~40℃ red/0℃~50℃ black and white Storage temperature: -25℃~70℃ Working humidity: 40%~70% Package Includes: 1PC Electronic shelf label note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution