P- Pea Comb
The pea comb gene is an incomplete dominant gene that causes the comb to become three low, parallel ridges. Also, it decreases the size of the wattles.The pea comb is often also associated with a dewlap of skin between the wattles.
Pea Comb: P/P
Here you can clearly see the smaller wattle size.
When the pea comb is heterozygous for a single comb it produces an intermediate phenotype. A type of modified pea comb, the comb is much taller and messier, and the wattles aren't as small. I call this a "pingle comb."
Pingle Comb: P/p+
A Chrysanthemum comb is also a modified pea comb. It is just a pea comb that is bred to be extra big and gnarly, but the wattles remain small.
Chrysanthemum Comb: P/P
Finally, we have the cushion comb. As you can see, the pea comb gene has provided it's small size, round shape, and small wattles, while the rose comb gene provides its smoothness.
Cushion Comb: P/PR/R