I mostly use Tip Top Rema, but also used (and still carry some in my kit) a large patch from Weldite, which you can cut to whatever size you need. Good for temporary repair of tyre side walls when you get a cut or then the threads start to tear apart. I use it with the Top Rema glue, it has a very similar vulcanising (?) orange layer under the black rubber. It doesn't have the thin edges obviously but, cutting the corners of a square patch, I never had issues. Very economic to use...
I mostly use Tip Top Rema, but also used (and still carry some in my kit) a large patch from Weldite, which you can cut to whatever size you need. Good for temporary repair of tyre side walls when you get a cut or then the threads start to tear apart. I use it with the Top Rema glue, it has a very similar vulcanising (?) orange layer under the black rubber. It doesn't have the thin edges obviously but, cutting the corners of a square patch, I never had issues. Very economic to use...