This listing is for a pair of tyres only. "Eddy Current" is the name of Schwalbe's first tire specifically developed for the E-MTB - for All Mountain, Enduro and Gravity. Front 29 x 2.4 inches, rear 27.5 x 2.8 inches is the perfect combination. The two tire sizes combine their attributes as part of a coherent overall concept. The blocks are about 20 percent larger than on the Magic Mary, for example. This results in greater stability, more traction and longer durability.. Rear. Eddy Current Rear tires dig deep into the ground when you brake and converts the full power of the motor into propulsion during acceleration. The large footprint of the 2.8-inch-wide tire and the sturdy center blocks provide the necessary traction.