Help with building the field

I am with rookie team 3521, the Noble Nuts, and we have a problem with building the field. On the measurements of the raw materials it keeps saying we need AR of 1/2" thick plywood. Can anybody tell us what AR means?

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Shadow Hills HS, Team 3521
Noble Nuts

AR = ‘As Required’

I had the same question when first reading through it. I might be able to take a picture of our mock field and upload it tomorrow, if it would help. ::safety::

Thank you so much, we can now get started.