Here is what Innova has to say about the Pig:
 
The Pig is an overstable Putt & Approach disc. It is great for hyzer putting, sidearm approaches and backhand spikes. The Pig holds the line well, even in extreme wind conditions. The Pig features a Thumtrac® Rim for sure grips on sidearm throws and putts. It performs equally well for backhand or sidearm throws.