I have a few that look identical to these. They're HDPE, I use them for grain storage and am very happy with them.
I reckon they are rodent proof, I've had one in the hen house for over 2 years storing grain with no problems.
Loads of lads over on Jims use these as boilers and one of the (very)small micro owners that use the site ferments in 220L versions of the same, just saying <!-- s:lol: --><img src="{SMILIES_PATH}/icon_lol.gif" alt="

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