This box attaches to the underside of the surron LBX. It helps take the weight off your back while transporting the charger on your surron. I have been using it for about a month with no issues. The only problem is it does barely scrape off of big jumps. I used 2" velcro straps to attach it to the bike.
https://www.amazon.com/dp/B0B7XSKSVP?ref=ppx_yo2ov_dt_b_product_details&th=1
The author marked this model as their own original creation.