Yes, absolutely.
yes, but only available at plumbing supply stores.
It's pretty narrow. I would estimate around 3 or 4 mm.
That should work.
I'm not exactly sure what you mean, but this tool is flexible and the grabber on the end works by pulling back on the hand hold.
Yes
yes, but it is not recommended at it is very small and the length will not provide much use. best to use an auger for exterior drains.
The Grabber bottom is made of spring steel and also has 4 clays to grab debris - not exactly sure what you describe scum as - but if it is the debris/hair etc then the Grabber should help.
If the string has a small ball or bead at the end it should do the job.
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