Tannus Armour Tubeless Tire Insert - 27.5 x 2.1-2.6" SingleTannus Armour Tubeless Tire Insert 27. 5 x 2. 1 2. 6" Single. Tannus Armour Tubeless inserts are the result of years of top level multi cell foam manufacturing mixed with extensive professional riding experience. At the heart of Tannus is the patented Aither Technology; a multi cell foam compound that forms the structure of the Armour. The inserts are designed to displace small impacts while offering a spring like rebound for a smooth yet playful