The how to make video can be found on YouTube https://www.youtube.com/watch?v=CxsferaI-T8
You can buy the wheels here: https://www.pennelcomonline.com/en/Penn-Elcom-64mm--252-Recessed-Black-Corner-Castor-Black-Steel-W2065K/m-5906.aspx
You can buy the handles here: https://www.pennelcomonline.com/en/Penn-Elcom-Medium-Recessed-Handle-H7151Z/m-8498.aspx
Please email sales@yetitool.com if you'd like to buy the foam for the base of the X Beam Box
The clips to attach the body to the lid can be bought from any fixings retailer.