If casting the only blade you need is a Colorado #4 gold blade with a lip on back.For trolling I use mainly #5 Colorado and double willow blades.I sometimes will use #6 Colorado too.The colors for trolling vary widely.The past two seasons have not trolled harnesses as much.The 2015 fish we have been catching the past two seasons have been preferring spoons.But when we had trolled with harnesses,my go to setup was using the #2 tadpoles weights with #5 purple boxer Colorado blade and a chartreuse double willow blades.The harnesses actually worked well in 2017 when the lake was overrun with those short 2015 fish.The harnesses seemed to help us catch the bigger fish.It was probably more due to location but we were able to stay away from those schools of shorts and limit on better fish.On a side note...with this pandemic and having all this free time....my reply is getting long winded.Oh yeah,I have got most my blades at fishermen wharf.But all the bait stores have custom blades.