What breed is this?

[Elemental]

I have ten chicks that I thought were all the same age. But four of them are growing much faster. They have black feathers, black beaks, flesh coombs, black toes (except for parts of some middle toes which are white). They seem tame enough and I have not seen them bullying the smaller chicks. But I have forgotten what the guy at the feed store called them. Any help with identification?

I will try to get a good pic of one of them.

Thank you for any and all help.

 

[ancdwc]

They sound like black sex links. Some chicks just grow faster then others and sex link birds are made to mature faster.

 

[WalkingOnSunshine]

Can we see a photo? What color is the underside of their feet?

 

[Elemental]

Oops. I forgot to get a pic last night. I will definitely get a couple of good pics tonight. Including the bottom of their feet. Thanks for helping.