I bought some because I thought I was going to get guests to sign a birthday quilt I made for my friend but then I decided against the signing..I have experimented with them though...they have .1mm and up...they are super fine...I found the .1 was too too thin but that is what was recommended in the pattern...
These liners are pigmented ink...they are archival and acid free...so they are safe for fabrics..they are also waterproof on paper and photo safe...my package says that the cap can be left off for 18 hours without drying out..but I haven't tested that...my brand Staedtler...made in Germany...bought at Business Depot (in Toronto)