--- title: "Model Specification" slug: "model-specification-12" updated: 2026-06-15T06:04:14Z published: 2026-06-15T06:04:14Z canonical: "knowledge.akuvox.com/model-specification-12" --- > ## Documentation Index > Fetch the complete documentation index at: https://knowledge.akuvox.com/llms.txt > Use this file to discover all available pages before exploring further. # Model Specification | Model | S539 | | --- | --- | | Touch Screen | ✔ | | Relay In | 3 | | Relay Out | 3 | | Alarm In | X | | RS485 | ✔ | | Card Reader | 13.56MHZ & 125KHZ | | Wi-Fi | X | | Bluetooth | ✔ | | Temperature Detection | Optional | | Face Recognition | ✔ | | LTE | X | | USB | X | | External SD Card | X | ## Supported Card Types The device’s firmware should be 539.30.10.316 or higher: - Unencrypted ID Card: - EM4100 - EM4200 - Unencrypted IC Card: - Mifare Ultralight C/EV1 - Mifare Classic Compatible Card - Mifare Plus-S 2K - Mifare Desfire EV1 2K D21 - Mifare Desfire EV2 D42 - Mifare Desfire EV2 D22 - Mifare Desfire Compatible Card (CPU Card, 4-byte): Incompatible with SmartPlus NFC service. - NFC Type2 216 - NFC Type2 215 - Felica Card - SmartPlus APP NFC - Mifare Classic S50 4-byte Encryption-Compatible Card - Mifare Plus-S SL3 Encrypted Card - Mifare Plus-SE SL3 Encrypted Card - Mifare Desfire EV1 Encrypted Card(AES file encryption mode) - Mifare Desfire EV2 Encrypted Card(AES file encryption mode) - Mifare Desfire EV3 Encrypted Card(AES file encryption mode) - Akuvox Cards: - Mifare Classic 1K - Mifare S50-1K Card - Mifare Desfire EV3 Encrypted Card(AES file encryption mode)