Images:

gw2-whisper's-secret-warhorngw2-whisper's-secret-warhorn-2gw2-whisper's-secret-warhorn-3

Set:

Slot Item Name Trading Post Preview Code
Warhorn http://db.dulfy.net/item/63501 [&AgEN+AAA]

Where to Obtain:

Purchased from Order of Whisper vendor in Bloodtide Coast for 3gold60s. Must be Order of Whisper member