It's a cheap toy, I bought it twice and it worked fine for desoldering (and clean the holes) on simple stuff as psu, but with motherboards it was useless, also it's not made to be durable, the suction pump stopped to work soon enough.
This video may be useful:
https://www.youtube.com/watch?v=3AjMhqk4Pow

I don't know how cheap you're after but I have something like this and it works brilliantly. There are plenty of other similar devices - they use an air pump to provide suction rather than what I assume is a spring. Just place the nozzle over the lead and squeeze the trigger until the solder is gone.

Define "cheap", how much are you willing to spend?

I agree with the post above that this desoldering iron will only be good with single side boards or big holes, but will struggle a lot with multilayer boards, and almost useless with more modern the motherboards that have huge ground planes and tiny holes for the components.

If you want an effective desoldering tool without paying for pro equipment there's always the good old ZD-915 or its derivatives: https://www.amazon.com/Digital-Desoldering-St … l/dp/B07542D82F

Keep in mind that it's very cheaply built and needs to be cleaned very frequently to prevent clogging, but if used properly those Dallas RTCs will be no problem. I've desoldered stuff like ISA slots, VLB slots and CPU sockets with great results using one of these things.

EDIT: 🤣, davidrg beat me for a few seconds, clearly the ZD-915 is a common tool in the retro scene.

tried that cheap one with a famicom and it broke after some weeks of use.
i think i had to apply solder to the points before using it, to be more effective.

I bought a ZD-915 2 years ago, that one is a pleasure. but still those damn ground points are a pain sometimes. Not easy ... even with the ZD-915

for example with a ZD-915 i tried to remove a socket7 from a broken motherboard and all was good. Needed a clean socket7 as a replacement part.
then i tried to remove a socket 370 from another broken motherboard, and the pins were so thin that some broke, ill buy a new socket

I have a Chinese S-993-A I think is the model number and it works fine (prices have gone up since I snagged it).

I have one pictured, it's a bit better than regular solder iron + spring loaded solder sucker in a sense that solder iron is not in the way. But I used it only few times because tip wares out quickly. After 2-3 hours of use (not all at once, during these few times) it looks like someone took a bite out of it so now doesn't close around the hole that needs desoldering and so far I haven't found replacement ones, although it should be replaceable.

Thank you for your comprehensive answers. Now I know that I should invest in slightly more expensive equipment like ZD-915 or better.