The Availability parameter filters out of ItemSearch results those items that are unavailable. The
availability of an item can change rapidly. There is typically a discrepancy between
an item’s availability as reported by ItemSearch and the item’s
true availability, as reported by Amazon’s web site. For this reason, the
availability of items reported by ItemSearch and by Amazon’s
web site will be slightly different. Items that are “available” are classified on
Amazon’s retail web site as: