It's a Tricky SenkoŽ If the standard 5-inch 9-series SenkoŽ is dynamite, then the slender 5-inch 9M SenkoŽ is a loud firecracker. The 9M is custom made to compete and win in any trick worm or slender worm situation. What the 9M has that the others don't is it always produces that unique SenkoŽ characteristic of shimmying and shifting with tip quivering action.