There are clear standards in GB/T 3098.1, and the hardness value of bolts can also be found. That is to say, as long as the performance level of the bolt is provided, it is equivalent to defining the strength of the bolt.
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1pc Bevel Gear 1.5M 12/16/18/20/25 Teeth Bore 6/8/10/12/14/15/16mm Gear 90 Degrees Meshing Angle Steel Gears Screw M5 No Keyway
Aliexpress UK
Thread: M2.5 M3 M4 M5 M6 M8. Thread length: a variety of lengths are available. Material: Nylon. Due to the differences in shooting scenes and technology, there will be a chromatic aberration between the photos and actual colors.
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1-5X M2 M2.5 M3 M4 M5 M6 304 A2-70 Stainless Steel Large Size Oversize Super Big Slotted Truss Round Head Bolt Screw GB947
Aliexpress UK
Description: Features: 0.8mm pitch, M5 x 35mm flat head socket cap screw bolts. Designed with hex socket head and 316 stainless steel material. Used widely in the home,office appliance, communication equipments, ship assembly and other machinery industry.
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640PCS M2 M2 5 M3 M4 M5 Hex Screw Nuts and Bolts Assortment Kit Metal Fasteners for Repair
Aliexpress UK
Description: Phillips drive has an x-shaped slot that accepts a Phillips driver. Flat head is cone shaped for use in countersunk holes and has a flat top that fits flush with the mated surface. Machine screws are used with nuts or screwed directly into a threaded receptacle to fasten metal parts together. Measured from the underside of the head to the tip of the screw to obtain fastener length. If nuts are needed, use with nuts of the same finish and threading for proper fit.
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M2 M2.5 M3 M4 M5 M6 M8 M10 Hex Socket Screw A2-70 304 Stainless Steel Hexagon Button Cap Head Metric Machine Bolt Assortment Kit
Aliexpress UK
Countersunk head bolts (Machine screws), steel, bright zinc plated. Slotted for use with a plain slot screwdriver.
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GB37 A2-70 304 Stainless Steel T-Slot Chute Rail Track T Shape Type Rectangle Hammer Head Bolt Screw M5 M6 M8 M10 M12
Aliexpress UK
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10/ 20/ 50pcs Black White Nylon Plastic Phillips Pan Head Cross Round Screw Bolt M2 M2.5 M3 M4 M5 M6 M8 length 4-50mm
Aliexpress UK
The product is made of high strength A2 stainless steel, combined with electroplating process, featuring high toughness, anti-rust, good performance and high strength. -Material:A2 Stainless Steel.
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M2 M2.3 M2.6 M3 M4 M5 PT Pan Round Head Self Tapping Wood Screw Tail-Cut Phillips Cross Recessed Black Zinc Plated Steel
Aliexpress UK
Surface: Blackened.
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M2 M3 M4 M5 M6 Brass Heat Insert Nut Screw Set Grade10.9 DIN7991 Hex Socket Bolt Hot Melt Thread Inserts Kit for 3d Printer
Aliexpress UK