Update README.md

Author: nseidle

README.md

@@ -4,7 +4,7 @@ SparkFun RTK Firmware
 <table class="table table-hover table-striped table-bordered">
   <tr align="center">
    <td><a href="https://www.sparkfun.com/products/17369"><img src="https://cdn.sparkfun.com//assets/parts/1/6/4/0/1/17369-SparkFun_RTK_Surveyor-14.jpg"></a></td>
-   <td><a href="https://www.sparkfun.com/products/15005"><img src="https://cdn.sparkfun.com//assets/parts/1/7/2/4/1/18019-SparkFun_RTK_Express-09.jpg"></a></td>
+   <td><a href="https://www.sparkfun.com/products/18019"><img src="https://cdn.sparkfun.com//assets/parts/1/7/2/4/1/18019-SparkFun_RTK_Express-09.jpg"></a></td>
   </tr>
   <tr align="center">
     <td><a href="https://www.sparkfun.com/products/17369">SparkFun RTK Surveyor (SPX-17369)</a></td>