The multi-function key is made of high-hardness metal material, which is strong and durable, not easy to be damaged, not easy to be corroded and oxidized, and has a long service life. The multi-tool key is very light and compact. It can be placed just on the key ring or in the wallet, which can provide convenience for your daily life. Features include closing wrench, hand hole, bending/bicycle wheel wrench, back hex wrench, bottle opener/hex wrench, serration/file/shear Line tool, measuring ruler/3cm, back measuring ruler/1 inch. It can be used for hiking on trails, fishing in the lake, cycling on the top of the mountain, camping in the basin, doing things around the house, and also for outdoor activities, such as outdoor camping, adventure and other activities.