Limited encoding options for this format. Facility Code = 249 only.  Number Range Available: 120,001 thru 524,287 only. Numerous options available in our RapidPROX® line. Click on the image above for more information.

The HID ProxKey III Key Fob programmed in H10304 37-bit format with facility code 249 is designed for access control systems that require a very specific credential structure with a fixed facility code and defined card number range. In this format, both the bit structure and facility code are predetermined, meaning the available credentials are limited to a controlled pool of card numbers within facility code 249. Because of this, it is essential that any replacement or expansion fobs match the exact format and facility code to ensure proper system recognition and avoid credential conflicts.

The 37-bit format provides a larger numbering capacity than standard 26-bit formats; however, when paired with a fixed facility code, the usable range is confined to a specific sequence assigned to that facility. This makes the H10304 format highly structured and predictable, but also dependent on maintaining consistency when ordering additional credentials. Operating on reliable 125 kHz proximity technology, these key fobs deliver consistent, contactless performance in a compact, durable form factor—ideal for everyday use in commercial, industrial, and institutional environments where format precision and controlled credential management are critical.