Prototype Four
All of the manufacturing kinks had been worked out in the previous attempts. A few design changes needed adjusting from the third prototype, but nothing that would create a fitting issue.
The holes intended to make installation easier had to be removed because they weakened the tabs too much. The width of the handle was also changed.
After seeing how easily the mounting tab on the third prototype bent, it became clear that having any size hole in this area would weaken the part too significantly. It is unfortunate because it makes the installation process slightly more complicated, but it was a necessary design decision in favor of the strength of the part and safety of the user.
After rigorous material testing, making the handle wider ensured that it would not bend.
