USP file extension is for PageMaker Printer font with U. S. ASCII extended character set
Similar to USP
A21 - Soundweb Firmware File
A2A - APLASCII EISPACK file
A2A - IBM Voice Type Language Vocabels File
A2A - Sharp APL Workspace Export File
A2B - A2B Player Playlist
A2M - AudioToMidi Settings file
A3 - Unrelated Inventions Audiotools Show Log
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