How to submit request where request inside binary file

Hi,

I need to send a request that uses a binrary file attachment.

In postman, I simply enter the URL, and to make it work, in the Body tab, I select 'Choose File' and 'Binary' radio and browse to the binary file.  All works a treat.  However, not sure how I can do this in LoadRUnner?  Am thinking along the lines of a web_custom_request but not sure where even to start.

Many thanks,

J