Comelit, Videx & EU Intercom Fobs: Which Are Copyable

The European Intercom Landscape

Italy and the United Kingdom dominate European residential intercom manufacturing. Comelit and Urmet are Italian brands with deep penetration across continental apartment blocks; Videx is a UK-headquartered manufacturer widely installed across British and Irish multi-tenancy buildings; CAME supplies both intercom and gate-automation hardware across southern Europe. All four reached market before proximity access credentials were standardised, so each developed its own credential approach rather than adopting a common open format.

The practical consequence for residents and facilities managers is that replacement fobs are not interchangeable across brands, and even within a single brand the correct credential varies by installation generation. A Comelit block installed in 2008 may use a different subsystem than a Comelit block fitted in 2018. Identifying the subsystem — not merely the brand — is the essential first step before ordering any replacement.

These credentials are also notoriously difficult to source at the building level. Installers often hold the only supply, and per-fob prices are significantly higher than equivalent access-control credentials from commercial suppliers. The intercom and residential entry segment is precisely the niche where a knowledgeable compatible-credential supplier adds the most value.

Comelit SimpleKey and Videx 955 Decoded

Comelit's residential proximity product line centres on the SimpleKey platform, designated SK9050 for its most widely distributed fob. The Comelit SimpleKey SK9050 compatible fob operates at 125 kHz and, in most installations, encodes a 26-bit Wiegand-derived UID on an EM4100-family chip. That EM4100 encoding is an open, publicly documented standard — the reader simply receives the chip's fixed UID and passes it upstream to the panel whitelist.

Videx's proximity fob is designated the 955 series and operates on the same 125 kHz band. The Videx 955 proximity fob compatible credential uses EM4100 encoding in the majority of installations found in UK and Irish apartment blocks, though later installations introduced MIFARE-based readers. The 955's physical form factor — a compact ISO-card-thickness fob — is distinctive and the chip technology is embedded in the fob body rather than a removable carrier.

Urmet fobs, particularly the Urmet 1125/50 compatible token, are 125 kHz EM4100 in their baseline configuration and share the same open-standard encoding. CAME intercom credentials, including the CAME TST01 compatible card, also follow 125 kHz EM4100 architecture in residential intercom applications, separate from CAME's gate-automation transponder cards which use a different format entirely.

EM4100/UID vs Secured MIFARE: What Is and Is Not Copyable

The single most important variable for any European intercom fob is whether the credential is 125 kHz EM4100/UID-based or 13.56 MHz MIFARE-based. The guide to 125 kHz vs 13.56 MHz identification covers the physical and reader-level tests in detail, but the short version is that 125 kHz fobs respond at a greater read distance and feel slightly different from 13.56 MHz fobs when held near an ISO/IEC 14443 reader. A smartphone NFC scan that returns no result strongly suggests a 125 kHz credential.

Open EM4100 credentials and MIFARE fobs programmed only with a freely writable UID can be reproduced on T5577-based or UID-writable blanks, because the reader is checking only the broadcast identifier, not any cryptographic challenge-response. The blank is programmed to broadcast the same UID as the original, and the panel whitelist sees an identical credential.

Secured MIFARE credentials — those where the panel has written sector data protected by AES or proprietary keys — operate differently. The reader issues a cryptographic challenge that the credential must answer correctly. A compatible blank for these installations is a credential the panel itself enrols, writing its own sector keys onto a blank that supports the correct MIFARE variant. The compatible vs genuine access cards guide explains this enrolment model in detail. Security ID Systems supplies both categories: writable blanks for open-standard systems, and enrollable compatible blanks for secured MIFARE installations.

Producing a Compatible Intercom Fob

For EM4100-based installations — the majority of Comelit SimpleKey, Videx 955, standard Urmet, and CAME intercom deployments — the production process requires the UID from a working credential, a T5577-based blank fob in the correct form factor, and programming to transfer that UID to the blank. The blank then presents identically to the panel. This is the same process used for 125 kHz LF proximity credentials across commercial access control, the difference being the fob body dimensions specified by each intercom manufacturer.

The format identification guide walks through the steps for reading UID and confirming encoding modulation — important because some Videx and Urmet installations use HID-compatible 26-bit encoding rather than raw EM4100, and the distinction matters for blank selection. Providing a working original fob to Security ID Systems, or supplying the UID string and confirmed encoding from a professional reading tool, is the most reliable route to a correctly specified compatible.

For MIFARE-based Comelit or Videx installations, the blank fob supplied must match the MIFARE variant the panel supports — Classic 1K, Classic 4K, or Ultralight — and it must be presented to the panel's enrolment function rather than programmed externally. Security ID Systems ships compatible enrollable blanks for these systems and can advise on the correct blank variant when the panel model is supplied. Gate-access credentials from the same brands, such as the CAME and BFT gate transponder card compatible, follow a separate transponder format and are sourced distinctly from the intercom fob range.

How to Identify and Order Your Intercom Fob

The fastest reliable identification path is to supply the panel model number — found on the main intercom unit inside the building entry, often on a label behind the handset cover or on the door-release controller in the electrical riser. The panel model maps directly to the credential subsystem in most cases. Where the panel label is inaccessible, the fob's frequency can be determined with an NFC-capable smartphone: 13.56 MHz credentials will be detected by the NFC reader; 125 kHz credentials will not be detected. Older buildings almost universally use 125 kHz.

When ordering, provide the panel brand and model if known, the frequency if confirmed, any UID string already obtained, and the quantity required. Security ID Systems stocks EU intercom fobs covering Comelit, Urmet, and Videx LF variants and the Urmet 1125/50 intercom token compatible for the most common Urmet panel series. CAME intercom-specific credentials and the CAME TST01 BPT compatible card for combined intercom-gate panels are also held in stock.

Building managers sourcing fobs for multiple residents should note that most EM4100-based panels maintain a simple UID whitelist with no upper limit on enrolled credentials. Compatible fobs can be added to the whitelist without specialist equipment in most cases — the same enrolment procedure used for original fobs applies to compatible blanks. Contact Security ID Systems to confirm compatibility for your specific installation before ordering. Security ID Systems is an independent manufacturer and supplier of compatible access-control credentials and is not affiliated with, authorised by, or endorsed by Comelit, Videx, Urmet, or CAME.