The latest wheel from Atom features a full urethane front supported with a large back mini-core.  The shorter size wheel is good for quick accelleration and short sprints.  Great in between wheel if you're looking for more grip than the Stinger, but not as soft as the Poison.  

Available in two hardnesses: 

59mm (high) x 38mm (wide) - 91A (red)

59mm (high) x 38mm (wide) - 88A (blue)