How do the self sharpening eyeliner work?

I just got 2 differnet self sharpening eyeliner. I tried out maybelines unstoppable eyeliner and tried to sharpen but it wouldnt work. I got Loreal's self advancing eyeliner--i havent used it yet, but how does it sharpen? I twist it but nothing happens..How do the self sharpening eyeliner work?
Try twisting the other way


Maybe theres a button on click thing?


;)


They do work, usually you just have to twist it.How do the self sharpening eyeliner work?
its technicly not ';self sharpening'; but when it starts to get dull you twist it up like you would with lip stick except when you twist it up it clicks into place..I find it extrememly convieniant because you never have to sharpen it and its not a big pencil thing.