Red-neck

Color and pattern male

Head: dark orange-red.

Neck-hackle, shoulders, back and saddle-hackle: orange-red.

Tail, primary- and secondary-flights, front of neck and breast: entirely green-glossy black.

Belly, thighs and rear-end: black.

Down: greyish-black.

Serious faults

White in any part of the plumage. Excessively faded or broken color in the red feathers. Black spots on the back. Breast or back  too heavily laced. Visible wing-triangle.

Faults

The above serious faults occur to a lesser extent.

Color and pattern female

Head: red.

Neck-hackle: red, some pattern is permitted.

Shoulders, back, saddle, tail, front of neck and breast: entirely glossy green black.

Belly, thighs and rear-end: black.

Down: greyish-black.

Serious faults 

Clear pattern, except in the neck-hackle.

Faults 

The above serious faults occur to a lesser extent.

Genetic code: https://kippenjungle.nl/Overzicht.htm

Website with all available information regarding chicken genetics including the chicken color calculator.