Solid rivets, sometimes called aircraft rivets, are a solid piece of metal with a large head on one side and a straight shaft. They are installed by sliding them in a hole slightly bigger than the shaft, then deforming the protruding shaft to 1 ½ times its size, so it is tight and cannot pull out. They differ from pop rivets in that they are solid, therefor stronger, and use a buck bar and pneumatic gun to install them instead.