Visual hets would be like:
Yellowbelly is a visual het for Ivory
Mojave is a visual het for Blue Eyed Lucy, along with Butter, Lesser, Mocha, Russo, and a few more
Fire is a visual het for Black Eyed Lucy
Het Red Axanthic is a visual het for Red Axanthic

I'm sure I'm missing a few others but basically a visual het is an animal that is its own morph that when combined with it's self or something genetically similar it creates a different morph, but it will be a like a super form not like something created from just two regular co-doms like a spider and pinstripe.

I hope this doesn't sound to confusing.