Bulky-body craw made a mix of double density plastic, including amino acids and shrimp taste/scent.
The lower concave part features a higher salt concentration than claws and the rest of the body. That cupped part helps getting longer casts and diving, with a more controlled fall but still erratic.
The claws, having more buoyancy, along its asymmetric antennae bestow lots of vibration.
The side appendices, apart from helping the lure to keep longer on the fish mouth, help stabilizing the fall and add subtle vibrations.
Upper side allows keeping the hook point out of the plastic, this way you'll be able to set the hook easily yet keeping it snagless, improving the lure's shelf life.
You can even remove the claws and you'll get completely different action, with an even more erratic fall for those overfished bass that are used to vibrations and appendices.