Mini stands for mini chain or .043[1.1mm] chain. New lightweight bar 25% lighter than comparable bars and comes in both 3/8 picco [lo pro] or 1/4 with the difference being it is running .043 [1.1mm] chain rather than the standard .050[1.3mm]. This gives a narrower faster cut. If you are running the 1/4 .043 chain ensure you have a 1/4 drive sprocket.