So far, I just love this feeder. I filled it with the hot seed, and so far squirrels don't touch it. But all the other little birds line up on the tree branches to get a turn. I don't think that the squirrel would be able to get seed through the tiny openings even if I put in regular seed, but he might be tempted to knock it to the ground. I filled with some mixed seeds, and the larger nuts will likely not come through the holes. Next fill will just be sunflower/safflower. Love the color, too. I take bird photos, and it makes an attractive background. I'm about to order another one!!