The ACR39U and ACR40U are both USB contact smart card readers from ACS with a single full-sized ISO 7816 card slot, CCID/PC/SC compliance, and EMV Level 1 / PBOC Level 1 certification. The ACR39U is obsolete — independent reseller documentation lists it on an official obsolete-products page, and ACS positions the ACR40U as its evolution, adding a second LED, on-device user data storage and remote firmware upgrade support. The ACR40U is also smaller, lighter, adds a USB Type-C option, and adds iOS/iPadOS driver support. For new purchases, use the ACR40U; if you're maintaining an existing ACR39U fleet, see the compatibility notes below before mixing hardware.
| Feature | ACR39U (ACR39U-UF) | ACR40U |
| Product Type | Full-size USB contact smart card reader | Full-size USB contact smart card reader (newer generation) |
| Status | Obsolete | Current — ACS's active replacement for the ACR39 line |
| Dimensions | 72.2 × 69.0 × 14.5 mm | 55.0 × 65.0 × 9.0 mm (Standard) |
| Weight | 65.0 g | 40.0 g ± 5.0 g (Standard) |
| Interface | USB Type-A only | USB Type-A and USB Type-C |
| Cable Length | 1.5 m (non-detachable) | 1 m (non-detachable) |
| Card Slot | 1 full-sized ISO 7816 slot | 1 full-sized ISO 7816 slot |
| Supported Standards | ISO 7816 Parts 1-4, Class A/B/C | ISO 7816 Parts 1-4, Class A/B/C |
| Protocol | T=0, T=1, memory card support | T=0, T=1, memory card support |
| Special Card Support | Mykad, CAC, PIV, J-LIS, SIPRNET | Mykad, CAC, J-LIS, SIPRNET |
| PC/SC | Yes | Yes |
| Certifications | EMV L1, PBOC L1, WHQL, J-LIS, TAA; CE, IEC/EN 62368, FCC, VCCI, UKCA, RoHS, REACH, KCC, UL, BIS | EMV L1, PBOC L1, WHQL, J-LIS, TAA; CE, IEC/EN 62368, UKCA, FCC, VCCI, RoHS, REACH, WEEE, UL 62368, KC |
| OS Support | Windows, Linux, macOS, Solaris, Android | Windows, Linux, macOS, iOS, iPadOS, Android, Solaris |
| Windows Driver | Legacy ACS Unified Driver | Newer ACS CCID driver |
| Extra Features | Not specified in available documentation | 2 status LEDs, firmware upgradable, on-device user data storage; Premium configuration adds a stand |
| Durability | Rated for 200,000 card insertion cycles | Not specified in available documentation |
Only specifications confirmed via ACS manufacturer documentation are shown. Cells are left descriptive rather than guessed where a figure isn't published.
The ACR39U is a USB contact smart card reader from ACS with a full-sized ISO 7816 card slot, EMV Level 1 and PBOC Level 1 certification, and support for Windows, Linux, macOS, Solaris and Android. BSD InfoTech has an existing ACR39U-UF setup guide for the Android-compatible variant it supplies.
The ACR40U is ACS's newer compact USB contact smart card reader, covering the same core use cases as the ACR39U with a smaller footprint, USB Type-C support, iOS/iPadOS compatibility, and firmware upgradability.
Only if you're maintaining or extending an existing ACR39U deployment and need matching hardware. Since it's obsolete, we don't recommend it for new purchases.
For any new deployment, or if you want USB Type-C connectivity, iOS/iPadOS support, or a smaller physical footprint. The ACR40U is also available in a Premium configuration with a stand accessory — see the ACR40U product page for details.
Both readers are PC/SC compliant, so most PC/SC-based applications should work with either with minimal change. However, they use different underlying Windows driver packages (the ACR39U uses ACS's legacy Unified Driver, the ACR40U uses the newer CCID driver), so re-test any code that installs or references driver files directly rather than going through PC/SC.
If you're replacing ACR39U units already in the field, verify your application against the ACR40U's driver before a full rollout, and note the physical size difference if the reader is mounted in a fixed enclosure or kiosk. Contact BSD InfoTech for a migration plan and genuine ACR40U supply.
BSD InfoTech supplies both the ACR39U and ACR40U across India, including bulk and dealer orders. Use the enquiry form below, or on either product page, and specify quantity and which reader you need.
Review the ACR40U's full specifications, including Standard and Premium.
View ACR40U