Animal ear: Product Name: Biological built-in electronic tags EM Series electronic tags EM4100 or compatible products developed by the chip. The operating frequency is 125KHZ, 64 laser programmable ROM, a non-contact, passive, read-only RFID tags. This series of products in plastic or resin encapsulated, waterproof, dustproof, corrosion resistance, high temperature, long life and small size. Standard features frequency response: 125 ± 6khz tag capacity: 64bits read and write features: read-only Weight: 1.0g Product Size: Φ 3mm × 12mm operating temperature: -40 ℃ ~ 85 ℃ Storage Temperature: -55 ° C to 100 ° C reading distance : 2 to 6 cm Usage: biological identity. Used in the field of animal management, population breeding, disease prevention, quarantine, rare species tracking.