Built on Gamakatsu EWG 60 degree hooks in size 3/0 or 4/0. We’ve experimented with jig head shape and different hooks for over a year and have found the perfect stupid tube jig. The round ball head makes it easier to install the jig inside the tube especially in the bigger sizes (up to 3/8oz). The 3/0 hook works great in 3.5″ tubes and the 4/0 is better for 4″ tubes. Thin wall tubes are best for the stupid tube technique. Sold in packs of 5.