The number available to ship today is for orders placed by 8:30 AM Pacific time.
For orders that can ship complete from one warehouse, "Today" is extended to 1:30 PM for Oregon and Nevada, and 11:30 AM for Utah.
If you click the link to "Show all four warehouse quantities", you can see exactly how many items can ship from each warehouse.
The number available to ship in 1 or more days is for orders placed today by 1:30 PM Pacific time.
Example: If our site says "0 Tomorrow" and "5 Tuesday", if you order today by 1:30 PM Pacific time we can ship up to 5 of these items by Tuesday from one of our warehouses.
