Published at: 2026-09-17

Relationships between products, items, and units

Use this reference to understand how product, item, and unit objects are created, related, and maintained.

Products and items

When the item feature is disabled, only the product object exists. The product directly maintains its name, category, unit, and other basic information.
After you enable the item feature, products relate to items. The item maintains shared product information, and the product carries business-specific information.
A nonvariant item maps to one product.
A variant item can map to multiple products. Each product maps to one variant combination.
When you create a variant product, the system generates its name from the item name and variant values. Product maintainers can edit the name.

When multiple units are disabled, a product supports only one unit of measure.
After you enable multiple units, the system adds a unit object. Products can relate to multiple units and maintain conversion relationships.
Conversion ratios must be unique within a product, and each product must have at least one base unit.
For a variant item, the item centrally maintains multiple units. The product page only displays the item’s multiple-unit information.

Information type	Maintained by	How it appears on related products
Product name	Product or item creation flow	The system can generate a variant product name from the item name and variant values. You can edit the name.
Product category / unit / multiple units	After items are enabled, either side can maintain a nonvariant product during creation; a variant product inherits the item. During editing, the item is the single source. In the basic mode, the product maintains these values.	A nonvariant product can set values independently during creation. A variant product inherits the item, and the product page locks these values during editing. Update the item to synchronize them.
Variant combination	Item	Each variant product maps to one variant combination.
Business information	Product	The product carries this information for use in sales, quotes, orders, contracts, and other business records.

Related products stay synchronized after you update shared category or unit information on an item.
All related variant products update after you change multiple-unit settings on an item.
Under a nonvariant item, the product can maintain its own multiple-unit information according to the current configuration.
To change shared information or multiple-unit information for a variant item, open the related item object.