- Not available on that edition (the reason is in the tooltip)
- Depends on the setting, your class or another addon (details in the tooltip)
What it does
Checks how many of the item you choose you are carrying in your bags, compared with the quantity you set. For an item set, only the first item in the list that you carry is counted, and carrying none counts as zero.
Why you might use it
Compares how many of an item you have in your bags. Use it to keep reagents and consumables topped up, such as a Mage conjuring water when supplies run low, or a Warlock finishing a target with Drain Soul while Soul Shards are short. With an item set, the count comes from the first item in the list that you are carrying, not the total of all of them. See also Item Available and Have Item Equipped.
Example
the number of Soul Shard you are carrying is less than 3
Settings
What each setting in the condition editor means, from the game's own help.
Item Set - This is a list of items to look for in your inventory. This list is ordered, the top found item in the list that you are carrying or wearing is what will be used in this condition. NOTE: this will NOT search for ANY item in the list that matches this condition, only the first item found will be used in this condition.
You can choose from either a pre-defined Item Set, by picking it by name from the drop down menu. You can edit these using the Item Sets configuration menu. Any item set in cyan is a global item set available to all your characters, otherwise they are available to this character only. If you do not want to set up a reusable item set, you can select Custom to specify an ad-hoc item set.
Edit - Edit the contents of the item set. If you have selected a pre-defined item set, you will be editing that item set, which may affect other usages of that item set (including on your other characters if it is a global item set). An item set must have at least one item in it for this condition to be considered valid.
Item sets are checked in priority order. Bag counts use the first carried candidate, not the sum. Availability, range and cooldown checks use the first carried or equipped candidate. Missing or restricted observations stay unavailable, including under NOT.
Operator - How to compare Have Item In Bags with the Quantity value. This comparison uses basic mathematical comparison operations.
Quantity - The quantity of Item you are carrying in your bags.