Same as when you use -x switch with 7-ZIP command line (-x=0 for store, -x=9 for ULTRA)
Copied for 7-ZIP Help file:
STORE - No compression.
Fast compressing: fast LZMA mode, 32KB dictionary, HC3 Match finder, BCJ filter.
Normal compressing: normal LZMA mode, 2 MB dictionary, BT4 Match finder, NumFastBytes is 32, BCJ filter.
Maximum compressing: maximum LZMA mode, 8 MB dictionary size, BT4 Match finder, NumFastBytes is 64, BCJ filter.
Ultra compressing: maximum LZMA mode, 32 MB dictionary size, BT4b Match finder, , NumFastBytes is 64, BCJ2 filter.
When using Solid, the size of solid block are:
Store 0 B
Fast 16 MB
Normal 256 MB
Maximum 1 GB
Ultra 4 GB