ACR122U is about 4 times cheaper than the ACR1281U-C1 model. https://s.click.aliexpress.com/e/_opZTvrc This demo software uses PC/SC wrapper classes for .NET to read card serial number. PCSC-Sharp library is wrapper that provides access to the Personal Computer/Smart Card. https://github.com/danm-de/pcsc-sharp Check out the ACR122U NFC C# Project for reading NDF card Tag ID. Download source code in the link below. https://www.instructables.com/ACR122U-NFC-C-Project/ https://www.sydesoft-blog.de/nfc-reader-acr122u.html When a NFC card is detected, it will call the OnCardInserted event and send the APDU command to read the serial number. Hope this will help someone starting to use #ACR122U Smart Card Reader. Thanks for watch!