---
product_id: 152469877
title: "UID7B1K S50 with 7 Byte UID Changeable Rewritable Smart IC Card for ACR122U-A9 Device Read Write (MF1K 7byte 5pcs) by XCRFID"
brand: "xcrfid"
price: "3 zł"
currency: PLN
in_stock: false
reviews_count: 2
url: https://www.desertcart.pl/products/152469877-uid7b1k-s50-with-7-byte-uid-changeable-rewritable-smart-ic
store_origin: PL
region: Poland
---

# Compatible with ACR122U-A9 Standard Size 85 x 54 mm 7 Byte UID Changeable UID7B1K S50 with 7 Byte UID Changeable Rewritable Smart IC Card for ACR122U-A9 Device Read Write (MF1K 7byte 5pcs) by XCRFID

**Brand:** xcrfid
**Price:** 3 zł
**Availability:** ❌ Out of Stock

## Summary

> Unlock the Future of Access Control! 🔑

## Quick Answers

- **What is this?** UID7B1K S50 with 7 Byte UID Changeable Rewritable Smart IC Card for ACR122U-A9 Device Read Write (MF1K 7byte 5pcs) by XCRFID by xcrfid
- **How much does it cost?** 3 zł with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.pl](https://www.desertcart.pl/products/152469877-uid7b1k-s50-with-7-byte-uid-changeable-rewritable-smart-ic)

## Best For

- xcrfid enthusiasts

## Why This Product

- Trusted xcrfid brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **📦 Value Pack:** Includes 5 rewritable smart IC cards for all your needs.
- • **📏 Perfectly Sized:** Standard dimensions ensure easy handling and integration.
- • **🔒 Enhanced Security:** Utilizes GEN3 Chip technology for reliable performance.
- • **🔄 Transform Your Access:** Easily change the UID for versatile applications.
- • **💻 Seamless Compatibility:** Designed exclusively for ACR122U-A9 devices.

## Overview

The UID7B1K S50 is a set of 5 rewritable smart IC cards featuring a 7-byte UID that can be easily modified using the ACR122U-A9 device. With a standard size of 85 x 54 mm, these cards are designed for seamless integration and enhanced security, making them ideal for various applications.

## Description

Please Kindly Noted : This card is GEN3 , And it ONLY supports the ACR122U-A9 device modify the UID number . We provide the PCSC Tool for ACR122U-A9 . Description 7byte UID. Works exactly like the M1k Card, with 16 Sectors and 4 Blocks each Sector, but the Sector 0 Block Zero known as Manufacturers Block where the Chip UID is stored, can be re programmed to any UID you wish.Applications: - Loyalty - Ticketing - Identification - Access ControlSpecifications Rewrite Times: 100,000 times Modulation: ASK Manchester coding Read Distance: up to 8cm (depends on the antena size)Material: PVC Dimensions: 85 x 54 x 0.84±0.02 mm

Review: UID NOT modifiable/changeable - The description states that this card is UID rewritable; however, this is not true. I attempted to write a saved UID, which is my apartment key, using my Flipper Zero and the NFC Magic app. After writing, I scanned the card’s UID, and it remained unchanged, confirming that the UID cannot be modified.
Review: Says programmed but doesn’t function, maybe I’m not smart enough - Copied key to a few and said written, but didn’t open any doors

## Features

- Please kindly noted : It only supports the ACR122U-A9 device modify the UID number!
- UID7B1K S50 with 7 byte UID Changeable Rewritable Smart IC Card
- It ONLY supports the ACR122U-A9 device read write . Through PCSC Card Tool . It doesn't support other device to modify the UID number !
- GEN3 Chip , UID7B1K with 7 Byte UID Changeable Card, Standard Size 85 x 54 x 0.84±0.02 mm
- Package Included : 5PCS UID7B1K S50 with 7 byte UID Changeable Cards

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B07QM1GWL6 |
| Batteries required | No |
| Best Sellers Rank | #543,289 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #292 in Commercial Access Cards |
| Customer Reviews | 3.0 3.0 out of 5 stars (7) |
| Item Weight | 1.13 ounces |
| Item model number | XC233 |
| Manufacturer | XCRFID |
| Package Dimensions | 3.94 x 3.62 x 1.02 inches |

## Images

![UID7B1K S50 with 7 Byte UID Changeable Rewritable Smart IC Card for ACR122U-A9 Device Read Write (MF1K 7byte 5pcs) by XCRFID - Image 1](https://m.media-amazon.com/images/I/41JMe7U5SBL.jpg)

## Available Options

This product comes in different **Size** options.

## Customer Reviews

### ⭐ UID NOT modifiable/changeable
*by N***R on January 3, 2025*

The description states that this card is UID rewritable; however, this is not true. I attempted to write a saved UID, which is my apartment key, using my Flipper Zero and the NFC Magic app. After writing, I scanned the card’s UID, and it remained unchanged, confirming that the UID cannot be modified.

### ⭐ Says programmed but doesn’t function, maybe I’m not smart enough
*by K***E on September 27, 2022*

Copied key to a few and said written, but didn’t open any doors

## Frequently Bought Together

- UID7B1K S50 with 7 Byte UID Changeable Rewritable Smart IC Card for ACR122U-A9 Device Read Write (MF1K 7byte 5pcs) by XCRFID
- Writable Dual chip UID Changeable MF1 1K with 125_LF T5577 Rewritable ID/IC Card for Copy Clone Backup

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*Product available on Desertcart Poland*
*Store origin: PL*
*Last updated: 2026-03-17*