How the compatible 4-byte CSN 32-bit (passthrough) works
The 4-byte CSN 32-bit (passthrough) is a dual-frequency credential operating on both 125 kHz LF and 13.56 MHz HF, so the compatible part must carry the correct data on whichever band your readers use. Its data structure is 32-bit raw card serial number passthrough, no facility code, no parity. When you present a credential, the reader decodes that exact structure and passes it to your access-control panel as a card number it recognises.
As a programmable blank, the 4-byte CSN 32-bit (passthrough) is the raw material the rest of the catalogue is built on. We supply it factory-fresh and rewritable on the Genuine NXP MIFARE Classic / T5577 platform, so you — or we — can encode it to emulate the proximity format your readers expect. It is the backbone of every 125 kHz compatible credential we ship.
To order, tell us the part number or format printed on your existing Standard / Generic card, along with your facility code and card-number range, and our specialists confirm the encoding before anything ships. Bulk and reorder quantities are welcome — pricing is a fraction of OEM list, and every credential is verified to read on your existing equipment.
Also known as
4byte CSN · 32-bit CSN passthrough · UID-only credential · serial-only card
Generic and all other brand and product names are trademarks of their respective owners. Security ID Systems is an independent manufacturer and supplier of compatible access-control credentials and is not affiliated with, authorized by, sponsored by, or endorsed by these companies. Brand and format names are used only to identify the systems our products are compatible with. MIFARE and DESFire are registered trademarks of NXP B.V.