FR4

Information from: http://bontrager.com/model/08447.

The FR4 is Bontrager's freeride tire for rough trails. Wet or dry, its ready to tackle rocks, roots and loose terrain.

Features

Tubeless ready optimized for use with Super Juice

Condition-specific compounds assure maximum control

Reinforced casing to handle the most aggressive riding styles

Big-volume freeride tire intended for very aggressive riding over difficult terrain in wet or dry conditions