Over twenty years ago, Saucony introduced a technology called the G.R.I.D. System that would be evolved over the next two decades. The system was designed to simultaneously absorb shock and control mediolateral motion. With this technology, almost 3 years in the making, we created the G.R.I.D. 8000 CL. One of the key components of the G.R.I.D. system is the G.R.I.D. Cassette located in the heel of the midsole. It includes blended composite Hytrel filaments molded in an interlocking configuration. Designed to work with the midsole in reducing shock and enhancing stability.