USB bulk charger wall mount shelf

I use a lot of rechargeable LED under counter lights to illuminate several display cases. I purchased a 10 slot bulk USB charger from amazon, but the cables took up a lot of desk space. I moved the charger to a wall shelf, but the weight of the cables caused the charger to flip off the shelf. I designed this shelf with holes on the shelf to drop the cables through and keep the charger balances. I am using it on a 10 port charger, but A 20 port would fit just as well, the holes will support more than on cable through each.

I err on the side of over kill, so I printed using PETG CF, however, I am sure PLA or plain PETG would be fine.