Typically measuring slide Serial Numbers     > 510410 = 64 bit                             >106174 = 64 bit

A 64 bit Bluetooth will sometimes have a sticker on it similar to the one above



**32 Bit dongles are digitally paired with the measuring slide and 

cannot be replaced seperately

If you have a 32 Bit Bluetooth Measuring Slide you will need the Ezurio driver software.  If it is already installed you will have a big bluetooth Icon on your Desktop or you can check your programs and features.  If you need it, you can download the attached file.

Image result for bluetooth icon picture

Below is an example of a bluetooth dongle.  

This is what provides communication between the measuring slide

and the computer. It will say Liard, TDK or Ezuiro