*SSR's:
The SSR Series of Super Swamper Radial/TSL tires is the next generation of light truck radial tires. This series has many of the OEM sizes for Sport Utility Vehicles and 4 Wheel Drive light trucks who do not want to modify their vehicles but still need the performance of Super Swampers. The design incorporates a slightly tighter tread pattern, siping for wet pavement traction and icy conditions, greater sidewall protection with traction features and is quieter running.
*TSL Radial's:
The Super Swamper Radial is the most aggressive light truck tire ever developed. It is designed for a very smooth ride at surprisingly low noise level.
*info taken directly from thier site:
http://www.intercotire.com/
Seems like they are pretty much the same tire, except for the tread and sidewall patterns...