Hi. I'm thinking blue Australorp or maybe even blue Orpington (since they are kinda fluffy).
But they're very small, it's very hard to tell a breed at this stage. In a month or so things might get clearer, but event then it will be hard to tell. In a couple of months, when their feet will have a more definitive color, look for the color on their soles. If it's yellow, they're not orpingtons or australorps. The sole should be gray-whitish-purplish. If their eyes remains very dark, almost black but the soles are yellow, you might have a Jersey Giant (especially if they will grow very large). If the eyes will become yellow or red, you probably have something else or a hybrid, event though hybrids rarely are blue in color, and it seems that they are blue-feathered.
