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These EM-4100 family products are designed to work with our RFID Card Reader (#28140) and RFID Reader USB 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. Features: EM4100 Family Passive Tags 125 kHz activating frequency Readable from 2 to 5 inches of RFID reader Discrete size 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. Compatible With: RFID Card Reader (Serial) RFID Card Reader (USB) RFID Read/Write Module (Serial)
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🇺🇸 Ship from USA · On Agora since 2026
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