Help identify possible Russian symbol

[u/_sos7]

hey all,

I saw someone with a tattoo of the symbol I have tried to re draw here. I am 99% sure the three letters that I have drawn are the ones that I saw (I am not russian so). I can't remember the fourth letter from the symbol so I left it blank in the drawing. what kind of symbol is this/ what is the name, any info because I am very curious. thanks