do those overnight heatless hair curling things really work?

hi! so i have mostly straight, slighly wavy hair but i recently cut it quite short (shorter than i wanted tbh 😭). i think my new short hair would look better if it was a little curly or at least wavy, but i don't want to use heat in any way.

i've seen those curling rod things online that are supposed to give you waves if you leave them in overnight.

do they actually work? how effective are they? if not, is there any other way to achieve this without heat? thank you!!! 😁

p.s. first time posting here but i love this subreddit. you're all lifesavers fr 🫶