Vibration by blade and small silhouette induces fish bite unconsciously!
Shalldus realizes the blade’s ability in shallow area.
The body has a flattened backside, which makes Shalldus come up more and more while swimming as it is retrieved. The abdomen side was designed to minimize the flow resistance, not to generate the pressure against its flouting movement. Thus, Shalldus can come up to the surface easily even on slow retrieving.
It has blade, but still flies far enough and then swims at shallow range right under surface.
Of cause, you can keep deeper range by pausing it before retrieving.