Roof Rack End Cap

Long story short, some how my end cap for my "Brightlines Cross Bars Roof Luggage Bars Roof Racks" purchased on Amazon a few years ago went missing either somebody needed one and ripped mine off or the it came off by itself, which I am not inclined to believe as these are pretty difficult to get off even with pliers. Anyways I designed replacements for my racks using Tinkercad. For outdoor durability this cap should be printed using PETG rather then the standard PLA.