Contact credentials
Contact chip memory cards
ISO 7816 contact memory cards in the SLE4442 / SLE4428 class (supplied as pin-compatible FM4442 / FM4428), used by legacy hotel locks, membership systems, metering and closed-loop stored-value applications. Available blank or personalized with printing and numbering.
For new deployments or authorised credential issuance. Existing secured cards are not copied.
What is an SLE4442 or SLE4428 contact chip card?
SLE4442 and SLE4428 are ISO 7816 contact memory chips — 256 bytes and 1 KB of EEPROM respectively, each write-protected by a PSC security code — long used in legacy hotel locks, membership and stored-value systems. American Key Cards stocks the pin-compatible FM4442 and FM4428 equivalents as gloss PVC cards, blank or printed and numbered, confirming which chip class your terminal expects before production.
Overview
About Contact chip
Long before contactless took over, the gold-pad contact chip card ran the world’s hotel locks, club memberships and prepaid metering systems — and an enormous installed base of that equipment still works perfectly, still reads ISO 7816 contact cards, and still needs card supply. The original Siemens/Infineon SLE4442 and SLE4428 chips have passed into history, but pin-compatible FM4442 and FM4428 silicon carries the torch identically.
We stock both classes as white gloss PVC cards, blank or personalized with printing and numbering. The two chips are not interchangeable despite identical appearances — 4442 carries 256 bytes with a 3-byte security code, 4428 carries 1K with different protection — so the first step of every order is confirming which one your terminal expects.
Technical details
Contact chip memory cards specifications
- Interface
- ISO/IEC 7816 contact
- Chip class
- FM4442 (SLE4442-compatible) / FM4428 (SLE4428-compatible)
- Memory
- FM4442: 256 bytes EEPROM · FM4428: 1 KB EEPROM
- Protection
- PSC security-code write protection (3-byte on 4442, 2-byte on 4428)
- Card dimensions
- CR80 ISO/IEC 7810 ID-1 — 85.6 × 54 mm, 30 mil / 0.76 mm
- Printing
- Dye-sub direct-to-card printable, with optional numbering
- Use cases
- Legacy hotel locks, membership, metering, stored value
- Compatibility note
- 4442 and 4428 are not interchangeable despite identical card bodies
Available configuration
Choose the form factor after the technology
Where it fits
Common Contact chip applications
Legacy hotel & hostel locks
Insert-style contact locks from major hospitality brands’ earlier generations still deployed across budget and independent properties.
Membership & loyalty systems
Club systems that write points or status data directly to the card’s protected memory.
Prepaid metering & vending
Utility, laundry and vending systems where stored value on the chip is the payment method.
Time & attendance terminals
Older workforce terminals with contact readers that outlive every software upgrade around them.
Before you order
How to order Contact chip correctly
- 4442 or 4428 — check twice
The card bodies are identical; the chips are not. Your terminal documentation or a working sample card settles it before production, because a wrong-chip batch reads as dead cards.
- The PSC code is a real lock
Both chips protect writes behind a programmable security code with a limited error counter. Whoever manages your system holds it; new cards ship with the transport code as standard.
- Contact pads take physical wear
Insert readers scrub the pads on every use. Gloss PVC with quality modules handles years of daily insertion — worth specifying over bargain stock that delaminates.
Questions we actually get
Contact chip FAQ
Is FM4442 really the same as SLE4442?
Functionally, yes — pin-compatible, protocol-identical replacements used industry-wide since the original chips were discontinued. Your reader cannot tell the difference, which is the entire point.
Can you preload data or value onto the cards?
We supply cards personalized with printing and numbering; data initialization is normally done by your system at issuance. For bulk pre-initialization projects, ask — feasibility depends on your system’s scheme.
Our hotel lock cards stopped being available — are these the answer?
Very possibly. Many discontinued hotel-lock cards were SLE4442-class inside. Send us a sample and the lock brand; identification is free and honest — if your lock needs something else, we say so.
Do contact cards work in badge printers?
Yes — standard CR80 bodies print normally. If your printer has a contact encoding station, it can also write to the chip in the same pass, PSC permitting.
Need help identifying the technology?
Send a photo of the credential and the reader model. We'll identify the format before we quote a compatible product.
Lifetime parts & workmanship guarantee on every card