There are 2 products.
POWER PRINCIPLE is a completely new. High-Copolymer, round, with a snap back as never before. The string has power, control at its best, supported by elastic additives.
The Signum Pro Thunderstorm is a axially twisted, decagonal string that offers excellent spin and control. This durable string has minimal tension loss while offering a comfortable, control oriented feel. This thinner gauge also offers a great playability.
