According to the CBSA’s website, to be considered a “part,” the item must meet criteria including that it has no alternative function, be marketed and shipped along with other parts of the product, needed for “safe and prudent use” of the item, and be “committed” to use with the unit.

Slip covers are the bare minimum for “prudent use” of anything with children.

Here’s hoping CBSA realizes their mistake and refunds her money.