A Product Unit is a unit of measure defined on a product - Each, Case, Pallet - with a conversion factor back to the base unit and optional per-unit pricing. Other systems call it a Unit of Measure (UOM), Pack Size, or Selling Unit.

Units model the reality that the same physical item is bought and sold in different pack sizes at different prices. A distributor's ERP may transact in cases while the storefront sells eaches; the conversion factor on the unit is what lets iPaaS.com translate quantities and pricing between the two systems without custom math in the integration.

Units are also referenced by kit components (a component points at a unit by name), which makes them a quiet prerequisite for any catalog that uses kits - the units have to exist on the component product before a kit referencing them can be built.