In TSM 4.10, we introduced a new option to group items by 'Item Level'. This means you can consider the item level of your craft, but ignore the secondary stat combination(s) of the craft, if you want to undercut any other auction or restock a set number of crafts regardless of those secondary stats.
It's important to note that you can put both the base item (the item without the random enchantment) and specific random enchants in groups. This means that if you have the base item in a group, you will still be able to put the specific random enchant in the same or a different group. When a module goes to look up what group an item is in, it'll look for the specific random enchant first, and then the base item second. If it finds the base item, the module will ignore all random enchants when conducting its operation(s) for the purposes of that item.
Selecting 'Base Item' in the 'Show ungrouped items as' drop down menu will show the item without reference to any of the BonusIDs that determine the item level, secondary stats, required level or any other information about the actual item. In this screenshot, the item in the inventory is item level 210, but shows in TSM as item level 175 to be added to a group. The item level 175 version cannot actually be crafted, Blizzard uses this as the 'base' and then adds BonusIDs for each of the real item variations. You generally should not group items by 'Base Item' for crafting purposes.
In the following example, 'Show ungrouped items as' is set to 'Specific Item'. This means all BonusIDs are considered including the item level, secondary stats and required level. If your intent is to undercut other item level 151 crafts with 40 Haste and 40 Mastery, then you would group the item as 'Specific Item'.
In the following example, 'Show ungrouped items as' is set to 'Item Level'. This means the BonusIDs that determine the secondary stat(s) are not included when adding the item to a group. Notice that there are now only 3 items 'Ungrouped' as 2 are of the same item level in the example. If your intent is to craft and undercut item level 151 crafts regardless of the secondary stat applied to the item, then you would group the item as 'Item Level'.