The Boonie hat has a long and distinguished career serving the US Military. The 100% rip-stop cotton and wide brim has a classic look. The metal screen vents keep you cool and adjustable chin strap keeps the hat in place. We have added a few innovations to this classic, that we think will set us apart from the rest of the crowd. We added a pocket under the crown, increased brim and made the hat adjustable with a pull cord. One size fits most.