Tyvek Waterproof Notebook is made using a high-tech fiber from DuPont USA - Tyvek. Unlike paper notebooks, it is waterproof, tough and durable, and can be used during severe weather or heavy rainfall, perfect for those who frequently participate in outdoor observation, outdoor occupations, mountain climbing, diving, wildness survival. The sheets used in the waterproof notebook is tear resistant. Under normal circumstances it is not possible to rip. It can only be written using pencil, oil-based ballpoint pen or pressurized pen. 99% of water-based rollerball pen are incompatible. The waterproof notebook can be used in damp environments. With this notebook, you can record your fleeting thoughts and inspirations down, even when swimming, jogging through rain, or showering. Whether it is used for mountain climbing schedule, outdoor all-weather memo, the waterproof notebook is your best tool.