The top piece of the feeder (cover) does not secure to the main housing, it just slides up and down on the hanging cord.  Squirrels somehow lift the cover, dislodge the front cage piece, and steel the block of food.  Birds are left with the crumbs on the ground.  I gave it a rating of 1 because its non-functional as a result.  The unit needs some type of clamping mechanism for the cover to make it functional.