-tzip default compression - LZMA or LZMA2?

[James JM]

Is the default compression for ./7z -tzip <filename> LZMA or LZMA2 or something else?

My understanding .zip is a file format where contents can be compressed by several different compression techniques or they don't have to be compressed at all.

7z l -slt <filename> not very informative it gives: Method = Deflate

[Igor Pavlov]

Yes, Deflate is default.
Deflate can be extracted by any zip program.
LZMA was added to zip specification later, and some zip unpackers do not support LZMA.

[James JM]

Thanks for that.