I used to do a lot of work for Aussie Post back in the late '80s after the demise of their own locksmith division. We had a contract to change post office boxes as they became vacated. Mostly we just rekeyed existing ones for them and let their maintenance people put them in themselves.
The reason they were initially restricted, was to require patrons to pay $50 for a spare key at the post office.....another money maker for them. After many years of no availability except the post office, Lockwood released blanks to a limited number of locky's australia wide. And then Edmonds (I think) copied the profile after the design registration ran out.
One One was a race horse, one one won one race, one two was a racehorse, one two won one too.
Disclaimer: Do not pull tag off mattress. Not responsible for legal advice while laughing.
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