This EM-4100 family product is designed to work with our Serial RFID Card Reader (#28140) and USB RFID Reader (#28340) and are considered passive tags. Each tag has a unique 10 digit ID, so multiple tags can be used in a single project and may be purchased from Parallax in any quantity.
EM4100 Family Passive Tags
125 kHz activating frequency
Readable from 2 to 5 inches of RFID reader
Note: In accordance with U.S. Patent Nos. RE40,145; 5,817,207; 6,036,099; 6,214,155; 6,514,367; and 6,557,766.