Thats a good idea !Survival emergency plastic rope/string...
Here are 2l bottle survival rope projects using my pocket knife.
Strong 10 m rope & +_5 mm from each of 2 x 2l bottles.
[Here the 2 x bottle's rope are stored inside another 2l bottle]
and also shown are another +_ 22 m continuous thinner rope [fishing?] [+_ 72 feet] & 2.5 mm from a single x 2l bottle.
My small fishing scale of 6 kg are pulled to the max without the +_ 2.5 mm plastic string breaking.
This is a nice survival skill to acquire, just for maybe one day.... !
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