Silo allows you to define the units that a particular Item in your inventory is purchased in. This is useful so that you can track the different kinds of packages that products come in when you order them.
For example, you may buy paper cups in cases of 100, while you may buy disposable gloves in a 1,000-pack.
You can also add and manage Units in the Settings area. Visit Settings > Units to see a list of all used Units. You can add a new Unit using the New Unit button. A dialog will appear:
Choose the name of the unit, and click Add to save it.
For products already in the inventory, you can modify the unit in the Item Details page. Choose the product you want to modify from the Inventory list, and click its Item ID. Scroll down until you find the unit dropdown:
This list will show all the units currently available. Click Save to save changes.