1710Pcs Metric Bolt Assortment M2 M3 M4, 21 Sizes 4Mm To 30Mm Upgraded Zinc ? [?????? ????????: ???? ??????, Various M2 M3 M4 Screws with Nuts and Flat Washers Meet All Demands] Nice set screw assortment kit. M2: Bolts are in 7 lengths: 4mm, 6mm, 8mm, 12mm, 16mm, 20mm, 25mm. Each length 20 bolts; 140 M2 Nuts; 140 M2 Washers. M3: Bolt length: 4mm, 8mm, 12mm, 16mm, 18mm, 20mm, 30mm. Each length 20 bolts; 140 M3 Nuts; 140 M3 Washers. M4: Bolt length: 6mm, 8mm, 10mm, 14mm, 18mm, 20mm, 30mm. Each length 20 bolt; 140 M4 Nut; 140 M4 Washer. 3 hex keys. ? [?? ????? ???? ???????, ??? ?? ????, ?????? ? ??????? ??? ? ?????, Screws Assortment Accord with Standardized Metric System] Different size of M2 M3 M4 screws and nuts total 1260pcs. 4MM to 30MM, short and long, more lengths to meet more need. Others: Maximum length is just 16mm/20mm/25mm. K Kwokker has more bolts, with a quantity of 420pcs, while others only have 200+ / 300+ bolts. ? [???? ????? ??? ????, ???????? ???? ?????? Screw Set, Practical Gifts for Family, Friends] K Kwokker: Upgraded Zinc Electroplated + Black Oxidized Version, 2 production processes, extended rust prevention time, no need to add anti-rust oil, cleaner and tidier. Others: Only black oxidized or only zinc electroplated version. K Kwokker screw is packed separately in a transparent bag. Storage: Assorted screws all are stored in one storage bin box, convenient for storing. ? [???? ???? ?? ????? ?? ?????????? ?? ???????? ???? ??????????. High Quality 12.9 Grade Alloy Steel] Nice Screws assortment, durable nuts and bolts. Extraordinary Technology Professional Durability. ? [???? ?????, K Kwokker Nut And Bolt Assortment Can Be Widely Used] in all kinds of precision machinery, classified instruments, instruments, electronic products, household appliances, communication products, locks, lamps, lights, toys, etc.