Thunder Bluff Pledge Collection

A Thunder Bluff Pledge Collection is a package of five pledge gifts, and is the first hierarchical combining of the pledge items given out by various Thunder Bluff NPCs during the Love is in the Air seasonal event.

All of the Love is in the Air pledge gift packages are non-functional as regards their name and picture. You cannot read a Thunder Bluff Pledge Collection.

Source
If you have five or more  in your inventory, right clicking on any of them will consume five and create a Thunder Bluff Pledge Collection.

Ingredient
A Thunder Bluff Pledge Collection is one of three Thunder Bluff pledge gift packages which are the ingredients of the Thunder Bluff Gift Collection.