The Ion2 is the largest diameter rope in the fusion range. It's unique design is manufactured by first twisting multiple colored fibers into a single sheath-strand and then braiding the sheath to create the speckled pattern. It's diameter is a great size for intermediate climbers looking to match a lightweight rope with performance while knowing that the diameter isn't TOO thin for a beginner belayer.
When getting ready to rappel or hanking your rope back up after the climb, fighting to find the middle of your rope can be a tedious task. The BiColor version of the Ion2 takes the guess work out by offering a bright change in color half way down the rope.