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By the way, I have none of the red requests for bullwinkle
Yes, you have one item from that set; even more: you're able to gift it by resending any item from that set.
I'll try to explain: every upgrade of main buildings (city hall, terminal, control tower) over level 6 needs multiple sets of 4 different items. Each game can gift one item from each set, but this item is hidden until particular building reaches the level prior to the level set is designed, so the player can't gift this item directly, but is able to send back the item if receives any item from such set.
It works both way: back and forward - every player can resend items for the buildings he/she was able to build in the past or will be able to build in the future.
Example: let's say I've just finished an upgrade of the control tower L6 and I'm preparing to upgrade it to level 7. The set of items needed to finish the upgrade consists of Airline Route Map, Headset, Monitor and Walkie-talkie. I can gift an ARM, (it appeared on my gift list after finishing upgrade of CT L6) but need also remaining 3 items. Now let's say your hidden gift is a monitor. You can't see it on your gift list, but when I send you an ARM, then you hit 'send back' button and I'll receive a monitor. After completing the upgrade of CT L7 the Airline Route Map will disappear from my gift list, but I'll still be able to resend it.
I apologize for that epistle; hope it's useful and clear enough