The TC-series protocol droid was a model of protocol droid very similar in appearance to the 3PO unit model of protocol droid. One TC unit designated TC-14 served the Trade Federation onboard the Lucrehulk-class LH-3210 cargo freighter Saak'ak during the Invasion of Naboo. Another TC unit designated TC-70 served the Hutt crime lord Jabba Desilijic Tiure as a translator during the Clone Wars. A TC unit designated TC-326 served in the Grand Army of the Republic during the Clone Wars and was made Archduke Poggle the Lesser's translator following his capture by Republic forces during the Second Battle of Geonosis.