Indiana "spec" or "speck" baits have easy to identify color schemes and body shape attributes. The variety of people who made and marketed "Hoosier Spec" baits shows how a given "type" of lure is expressed in different ways through time.
A White, Red and Black Al's Spec Bait
Body shape
The bait's body is usually 2 7/8 inches in length with its circumference narrowing front-to-back. The lure's belly has a shallow, uniform taper from head to tail. The head of the lure maintains a uniform, or close to width in the front for 3/4 to 1 inch, whereupon the back narrows down with the belly to a flat, slightly rounded-edge tail. This particular cut gives the effect of a fish-head with some shoulder. Different speck baits vary in the length of the shoulder or lack one altogether and have just a narrowing cylindrical body.
Speck Bait Body Shape Diagram
The lure's unique kisser is a signature feature. A slightly obtuse angle-cut into the lure's face creates a forward-thrusting forehead and a jutting lip-jaw. Some Al's Spec baits have compound cuts on the lip that form a cubistic kinda tongue protrusion. The line tie eye-screw is usually attached centrally, slightly above the jaw cut, anchored into just about where you would expect an esophagus. The face-cut on a speck bait, and the line-tie attachment to it, are features that help distinguish different kinds of speck baits.
A spec bait's color scheme is a telling attribute of this kind of bait.