Pencils will work great on Rite in the Rain All-Weather Paper but sometimes you need a pen. This All-Weather Metal Pen writes on wet paper and upside down, the pressurized ink cartridge performs in temperatures from -30F to 250F. The ink won't leak, evaporate, or blow up in your pocket. When closed the “Bullet” pen fits easy into your pocket, small pack, or even your wallet. 5 1/4” open (with cap attached to end), 3 3/4” closed, and a barrel diameter of 3/8". Back barrel. Black Ink. Refill cartridges available.