From Stud Pack.

Head to Flexispot and use code YTBXL650 https://bit.ly/4eekkYu for extra $50 off!

Custom thresholds and lots of other custom items: https://houzewoodshop.net/custom-wood-threshold-ramp-for-walkers-1/

Adjustable fire-rated door sweep: https://amzn.to/3TEtLrZ

Woodriver door miter clamps $85.00 each: https://amzn.to/3THjQlj
Woodriver door miter clamps $73.00 each at WoodCraft: https://www.woodcraft.com/products/woodriver-miter-max-corner-clamp
Door miter clamps $70.00 each: https://amzn.to/3XVm8jt

Stud Pack exterior door hanging video: https://www.youtube.com/watch?v=P4v6AcHLq2Q