2014 S Maxx
2011 Tacoma 4cyl ... edit: 2022 Tacoma 6cyl - oh yeah!

A_Little_T@b'll_Do_Ya

8.5mm / 5/16”. Use nylon rope when making your own cord for the rail.
Welded flap material for making your own visor, etc.:
https://www.amazon.com/gp/product/B010G1AXZO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Keder Rail “tarp trackers” for attaching a tarp or similar material to the Keder rail:
Keder Rail hangers (home made):
https://www.popupportal.com/threads/make-your-own-awning-track-hangers.63064/

I spray the rope of my awnings & the rail with Mclube Sailkote. https://www.mclubemarine.com/sailkote/Tampakayaker said:tighten the screws and use a silicone spray in the rail near the screw heads. Just a very small amount. Also while threading the tarp thru, pull out on it away from the back of the rail.

You can get the keder rope off of AmazonSimmons said:Thank-you Bayliss, Sharon, Dave, ChanW, Tampakayaker, and Marceline,I will order the smooth rope and sew the tarp to the flap. We also do see some of the screws might be raised a bit. We will check each one to see if they can be tightened. And then try the silicone or marine lube.I also like the idea of replacing with flush screws.Bayliss - Thank-you for the great URL links.We will test these ideas in the yard before our next camping trip.Tampakayaker- I do find that the tarp needs to be held with 2 hands, slightly pulling back on the left to keep it taught as we thread the tarp rope into the keder rail.. so, with more practice, and a smooth rope, hopefully all will go better next trip.