Grizzly T20795 - Unlimited Part Program Size
Provides the ability to run CNC programs larger than 4MB. Generally, this is needed for large 3D programs, and is not needed for 2½D job shop work.
You do not need this option to store many megabytes worth of G code programs on your control; only to run a job larger than 4MB.
Prior to software version 2.68, released in March 2010, the standard file size limit was 1MB.