I would suggest caution with them PB, they may not have a load bearing capacity suitable for carrying a baby (there is a lot of strain put on both the rings and the seams). Even thick rings may not be designed for loadbearing, depending on the metal composition and of the type of join. Not to say that the ones you have will not be suitable, but my experience with Bunnings staff is that many of them wouldn't really know. Marine grade rings will be suitable, as they are designed for loadbearing, but they are much heavier than the aluminium rings designed for babywearing. Which you can get from slingrings (US site), or theweewuns in Australia.

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