Substance Volume 3 Free is an expansion pack of all new sounds and samples for Caustic 2 and 3. You must have Caustic version 2 or 3 installed to use this. Contained within are 3 full Beatbox kits and 13 lead, pad, bass, and key PCMsynth presets. The sounds and samples have been created or optimized for Caustic. Most patches have been multi-sampled.