RG file extension is for 1bit B&W 4bit CMYK Raster Graphics format
Similar to RG
A01 - OzWin CompuServe E-mail/Forum Access SYSOP FileA01 - ARJ Multi-volume Compressed Archive
A10 - OzWin CompuServe E-mail/Forum Access SYSOP File
A11 - AIM Graphics file
A21 - Soundweb Firmware File
A2A - APLASCII EISPACK file
A2A - IBM Voice Type Language Vocabels File
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