PAC & Stanley 8x32 Fobs Explained

PAC, Stanley and Comelit-PAC Today

PAC International was founded in the UK and grew into one of the country's most widely installed access control brands, particularly in apartment entry systems, car park barriers and small commercial premises. Stanley Security acquired the PAC product line and continued selling readers, controllers and credentials under the Stanley-PAC branding across the UK and wider EU markets. Securitas Technology subsequently absorbed the Stanley business, and the credential and reader range is now marketed under the Comelit-PAC name — a brand consolidation that left millions of installed legacy readers intact and still in daily use.

For facilities managers and building contractors, the practical implication is straightforward: a site commissioned under the original PAC brand, later maintained by Stanley engineers and now supported by Comelit-PAC, will almost certainly still use the same NRZ 8-digit hex reader technology it shipped with. Credential procurement therefore spans three brand eras while the underlying format remains constant. PAC International built a durable ecosystem; the format outlasted every corporate rebrand above it.

The PAC 8x32 NRZ Hex Format Decoded

The PAC 8x32 designation refers to an 8-character hexadecimal identifier transmitted over a 32-bit data frame at 125 kHz. The encoding scheme is NRZ — each bit period represents either a high or a low state without returning to a neutral baseline between bits, which gives the format a distinctive bit-transition pattern that PAC readers are tuned to recognise and validate. This modulation choice is different from the Wiegand parity-framed binary used in many North American formats, and it is the primary reason that generic or multi-format kiosk duplicators frequently misread PAC credentials entirely.

Within that 32-bit frame, the token carries a facility or site value alongside the individual card ID. The site value allows a single installation to partition credentials into logical groups without issuing separate hardware — useful on large residential developments where multiple entrances serve different tenant populations. When ordering replacements or additional credentials, both the site value and the hex ID must be reproduced accurately; a correct hex ID paired with an incorrect site value will be rejected at the reader. Our guide on how to identify your access card or key fob format covers the practical steps for reading these values from an existing credential before ordering.

Why Kiosk Cloners Often Fail on PAC

High-street key-cutting kiosks and retail fob duplicators are configured to handle the handful of formats that dominate the consumer market — primarily EM4100 and basic Wiegand-encoded tokens. PAC's NRZ hex frame falls outside the detection range of most consumer-grade hardware, and the kiosk will either report an unreadable tag or produce a credential that carries a corrupted data string. The building manager then discovers the problem only when the new fob is presented at the reader and access is denied.

A second failure mode involves the underlying blank chip. Consumer kiosks typically write to low-cost generic blanks that do not support field-programmable NRZ encoding at the correct carrier frequency and bit rate. Even if the kiosk reads the ID correctly, the output credential may transmit at a timing profile the PAC reader rejects. For 125 kHz LF proximity credentials that must match a specific modulation standard, the write medium matters as much as the data content itself. Our technical guide to the T5577 programmable 125 kHz blank explains why chip selection is not interchangeable across encoding schemes.

Producing a Compatible PAC Fob

A correctly produced compatible PAC fob starts with a blank that supports NRZ modulation at 125 kHz and can sustain the PAC 8x32 timing profile under the RF field conditions typical of installed PAC readers. The programming step writes the exact 8-digit hex ID and site value from the original credential into the blank's user-data blocks, then locks the configuration pages to prevent accidental overwrite during normal use. The result is a fob that the PAC reader treats as a valid credential — not because it mimics an OEM product, but because it presents a correctly structured NRZ frame that the reader's decode logic accepts.

Fob body format matters in residential intercom and intercom and residential entry contexts. PAC credentials are issued in both standard ISO card format and compact token fobs for key-ring carry. If the building manager needs to distribute credentials to residents who are unlikely to carry a card wallet, a PAC compatible token fob in compact keyfob form is typically the more practical choice. Both form factors can carry an identical NRZ data payload; the choice is ergonomic, not technical.

Facilities teams managing multi-brand estates should also note that related UK-market formats require equivalent care. A Securitas-Stanley compatible access card for card-format installations follows similar procurement logic, and the Compatible vs Genuine Access Cards guide provides a grounded overview of what compatibility means in practice and what questions to ask any supplier before ordering.

Ordering Compatible PAC Credentials

When placing an order for compatible PAC fobs, the minimum information required is the 8-digit hex ID of each existing credential and the site value programmed into those credentials. If the site value is unknown, it can often be retrieved from the access controller's credential database or by presenting a working fob to a reader and logging the decoded output — most PAC and Comelit-PAC controllers will display the full data string in the event log. For bulk replacements covering an entire building or estate, a spreadsheet of hex IDs and site values enables batch programming and reduces turnaround time.

Security ID Systems supplies compatible PAC fobs individually and in volume, which makes the format accessible to managing agents handling a handful of resident replacements and to contractors commissioning multi-block developments simultaneously. We also carry compatible formats for adjacent systems found on the same estates: Jablotron compatible RFID cards for eastern European-sourced intercom panels, Came TST01 compatible cards for Italian-brand gate controllers, and a broad range of other compatible key fobs across every format for estates that have consolidated multiple access points under a single procurement contract.

Security ID Systems is an independent manufacturer and supplier of compatible access-control credentials and is not affiliated with, authorised by, or endorsed by PAC International, Stanley Security, Comelit-PAC, or Securitas Technology.