Do minesweeper crewmen's upper left sleeve patches differ from ship to ship? My dad was on a motor minesweeper, and I have been trying to find if his patch was unique to his ship, or if all had the same patch. The one I am speaking of has a light background, dark edge, and a mine in the lower center, along with a few other markings.

I found another minesweeper patch (1/3 each red, white and blue), but cannot find where it was worn. Could it have been on the right sleeve? It appears that my dad has something white on his right sleeve just above the cuff.