I think it's the space where you can fit a lock barrel should you wish to - the plastic cap pops off. I have some Thule that are similar, never bothered getting the locks
Ahh that makes sense, thanks.
@skinny started
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I think it's the space where you can fit a lock barrel should you wish to - the plastic cap pops off. I have some Thule that are similar, never bothered getting the locks