Fits the Ford F-150 Hard Roll Up Tonneau Cover (might fit other models that I'm not aware of): https://accessories.ford.com/products/f-150-2015-2021-hard-roll-up-tonneau-cover-for-5-5-bed-1
Print Instructions:
I got good results with the following:
Attribution/credit: faroutride.com
The author hasn't provided the model origin yet.