What are EID / RFID Ear Tag

EID or RFID electronic ear tags have special features besides just the ISO chip inside the small quarter size tags. 

The tags are activated when they pass within the transmission field of a reader. The tag then absorbs power from the reader and returns its unique 15 digit number back to the reader. There are two types of RFID ear tags. HDX (half Duplex) and FDX (full Duplex) ear tags and two versions of EID tags; official USDA 840 tags and the manufacturer coded.

Each EID ear tag has a 15 digit number around it. Think of this number like the VIN (Vehicle Identification Number) of a car. It is unique like a social security number for a person. The first three digits tell either the manufacturer or the country. 982 lets you know Allflex made the ear tag where 840 is the designation for the United States on official USDA ear tags.

Manufacturer vs USDA 840 - What's the difference?

Using USDA EID tags which start with 840 is the best option because they comply with all programs. An 840 EID tag is considered Official ID in all US states and is approved for interstate travel. With 840 USDA tags, a Premises ID number is required. See this link to get your Premise ID Number. You can use a EID tag that starts with a 9 without a Premise ID number but it will not meet most breeder or state regulations.  

Half Duplex vs Full Duplex - What's the difference?

Half Duplex (HDX) tags are white in color. They are better suited to transmit through metal interference such as metal and steel objects.

Full Duplex (FDX) are yellow in color and are good when read range is short.

Typical read range on HDX tags ranges from 38cm - 46cm (15" - 18")

Typical read range on FDX tags ranges from 35cm - 41cm (13" - 16").

However, FDX tags are more susceptible to interference from metal and steel objects such as head gates, panels, and squeeze chutes as well as fluorescent lights.

CCK sells readers that read both FDX and HDX ear tags.

Shop EID Ear tags.