Don't need a leader for your crank.Just attach to snap at end of line.Some people like to put weight right at end of line then run a leader to crank.If doing that my leaders are Seaguar 20lb flourocarbon at 7ft long.With swivel on one end that goes to weight or dipsey and snap on other end that goes to lure.Some people like to add a 2oz sinker to line either 20 or 50 ft from lure also.No leader needed when you do that.