Any idea on breed? Cream Legbar or Welbar?

[Highfield Farm]

Ideal has a limited selection of Welbars also.

The Ideal Welbars are contaminated with Legbar genes and the KK factor. This is as of 2024 and confirmed with other buyers from several purchases.

 

[NatJ]

The Ideal Welbars are contaminated with Legbar genes and the KK factor. This is as of 2024 and confirmed with other buyers from several purchases.

What is the "KK factor"?
(Abbreviations can be confusing sometimes.)