Twin blade sk5 carbon steel saw

one side- blade for cross cutting with an 11tpi blade

one side- blade for rip cutting with a 14tpi blade

rip cutting is cutting along the length of the wood

cross cutting is across the wood,

tooth geometry is very different with 

cross cut teeth being knife like for slicing through the wood fibres

rip cut teeth are chisel like for cutting through the fibers

1mm kerf