Nittaku Narucross EX rubber has the Narucross "cross system" with "Max Tension Technology" for the topsheet and sponge. Maximum tension results in Maximum tension without speed glue.

Narucross EX comes with two sponge options: Hard or Soft. 
The Soft version offers extra touch and control 
The Hard version offers extra speed with good spin.

Narucross EX Hard is used by US Team Member Samson Dubina. Samson says, "Narucross EX Hard is one of the world’s most powerful rubbers, hard enough for counterlooping yet soft enough for the best touch. Narucross EX Hard has the best control in it’s class of ultra-high-speed tensor rubbers. For me, the perfect combination is the Nittaku Ludeak blade teamed with Nittaku Narucross EX Hard!"

Samson Dubina holds these National titles: 
2009 US Nationals Men's Singles Finalist 
2009 US National World Team Member 
2008 US National Mixed Doubles Champion

Brand Nittaku   Type: Smooth   Speed: 91   Spin: 87   Control: 73   Hardness: 37.5   Sponge Thickness: 1.9,2.1