【High-Quality 12.9 Grade Alloy Steel】--- LuKaiSen Metric Bolt Assortment is made of premium grade 12.9 alloy steel for high Hardness and good corrosion resistance in harsh environments such as high temperature, cold weather and high humidity areas. And they also have superior oxidation resistance to ensure long-term use.,【Perfect Machine Screws Kit】--- LuKaiSen 1500PCS Metric Bolts And Nuts Assortment selected the most commonly used in life M2 M3 M4 M5 M6 five different sizes of screws are matched with the corresponding nuts, washers & lock washers, and each size of screws have 3 different lengths are 10mm, 16mm, 20mm, combined into a complete of hardware kits, which can solve your anxiety of finding matching parts. Meet the needs of different people, is a necessity for your home life.,【Excellent and Sturdy Storage Box】--- We want our customers to be simple and clear every time they use screws and nuts, so we put 30 types bolt, nut, flat washer, spring washer in 24 grids and each grid is marked with size label. We also provide 5 free relevant wrenches in our sets So you no longer need the extra purchase.,【Black Bolts Are Widely Used】--- Screws Nuts Set is suitable for professionals, amateurs, landlords, repairers and other DIY people. In daily life, you can use it in all kinds of precision machinery, classification instruments, meters, electronic products, home appliances, communication products, locks, lamps, lights, toys, etc. Perfect for drone construction, 3D printers, motorcycles, desks, remote control cars, remote control crawlers, remote control projects, DIY projects, etc.,【LuKaiSen Best After-Sales Service】--- We provide you with a 1-year warranty, a 30-day return guarantee and 7x24 hours after-sales service, any product problems can be quickly solved for you. If you have any dissatisfaction with our products, please contact us at any time and your needs will be met.