Review: Stretchy Silicon Food Covers

All right. One more review on plastic wrap alternatives.

My mum gifted me these stretchy food covers. I believe she ordered them from Ali Express and well, they're really not as good as I'd hoped they would be.

They actually don't work at all - as the photo demonstrates.
I don't know if anyone has any stretchy covers that work, but these ones are just wasting away in the bottom of the cupboard.