One unit is one item of stock. It is often used as a plural. The word unit is often used instead of the word product to avoid confusion when ordering several different kinds of products in the same transaction.

Examples:

I would like to order sixty units of your Sneaker Cleaning Kit.

We have six units left in stock.

Men's Society and Apothecary Department manufacture and sell handmade gift sets for men and women. We supply some of the world's most exciting retailers; ranging from recognisable names to niche concept stores. We don't have minimum or maximum orders and we make each order the easiest you've ever made.

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