They are commonly referred to as "Renogy Z Brackets". And agreed, much better then making your own.
I use these a lot and much prefer them to the big plastic lumps that most seem to use. If you want a better deal than that Temu one, then you can find a host of sellers on eBay and Amazon that sell probably better quality ones for less (don't get suckered by the supposed 37% discount)
If you want just one pair, get it free next day for less from this seller on Amazon -
https://amzn.to/4741FLd