There are (2) Polar Ice balls, one a urethane solid (green) and one urethane pearl (red). Both have a very simple weight puck. Both are just a step above a spare ball. However, I did drill one for a high rev customer who rolled a 300 with it, so they can do the job on a fried shot. I am drilling a pearl this week for a customer who wants a spare ball/dry lane ball. I hope this helps!
