This is one of the simplest bird feeders you can own. We have issues with squirrels that love to eat all the bird seed, so hanging this up in our garden doesn't deter the squirrels, but it makes it much more difficult for them since it will not hold their weight. The plastic mesh will hold most of the seeds except for the small grass seeds, which will fall if the feeder shifts too much. 
Because it is made out of wood, you may want to keep an eye on it with the weather.