It was the vortex hole that was active.This is a front heavy balance model that is symmetrical and has two vortex holes (3.5 mm in diameter) at the center of the body and 8 mm on the head side, and three star-shaped sculptures on the tail. The waves generated from the vortex hole appeal to the lateral line of the target and increase the activity.Equipped with vortex technology system.Front heavy balance.Silver phorogramm.S I P GLOW under the body.Thickness : 9.6 mm.