The Zen U features the new S35+ Urethane Solid cover with a modified version of the Meditate core, Meditate LD. This new cores has an RG of 2.56 and differential of 0.027. I drilled mine 5 x 4 x 2 and my first impressions of throwing this ball was WOW. I thought when I first drilled the Rubicon UC3 last year that it was super strong but this ZEN U blows it out of the water. It is easily 5 more than the UC3 and 10 more than my Pitch Black. It shapes kinda like traditional urethane balls at first but it continues through the back of the lane and pins way better than them and doesn’t go too forward. If anyone is looking for a new short pattern ball, sport pattern urethane or just something for the cliffed house shots. The ZEN U is your choice !