Stems mastering is exporting the separated tracks of a mix
Stems mastering are stereo recordings sourced from mixes of multiple individual tracks divided in groups (Drum Group, Percussion Group, Melody Group, Vox Group, etc.)
Export your tracks in the following file types: WAV / AIFF, 44.1 kHz / 48 kHz, 16 bit / 24 bit
Type the number of separated tracks which compose the song that you are sending me for your stems mastering