: This likely stands for AC-3 Video Rip or is a shorthand used by the group responsible for the encode (potentially related to groups that focus on high-quality audio/video standards).
: This is typically a unique identifier or internal tracking code used by a specific release group or indexer. sc12698-ACVR.part10.rar
: If you are receiving an error while extracting, you may need a "Rev" (recovery) file, which release groups often include to repair missing or damaged segments. : This likely stands for AC-3 Video Rip