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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304 Stainless Steel Lifting Eye Nuts/ Screw Ring Eyebolt Ring Hooking Nut M3 M4 M5 M6 M8 M10 M12 High Quality Lifting Ring Nut
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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1/2/3Pcs M2 M2.5 M3 M4 M5 M6 M8 M10 M12 M14 M16 Pure Titanium TA2 External Hex Hexagon Head Cap Screw Bolt Length 5-100mm DIN933
Aliexpress UK
Surface: Blackened.
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M2.3 M2.6 M3 M3.5 M4 M5 M6 Black Carbon Steel Phillips Truss Head Cross Recessed Mushroom Head Self Tapping Screws 10pcs-150pcs
Aliexpress UK
Material: Brass. Surface: Untreated.
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100pcs/lot 304 Stainless Steel CM Six-Lobe Torx Ultra Thin Super Low Flat Wafer Head Screw Bolt M1.6 M2 M2.5 M3 M4 M5 M6 M8
Aliexpress UK
Genuine JIS Oval-Round Countersunk Screws from Japan. These screws have the rounded countersunk head and are Genuine Japanese Industrial Standard screws- Made in Japan not China. M5 x 10, 12, 16, 18, 20, 25, 30 & 35mm.
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Head diameter 27mm Plastic Nylon T type Head Handle Thumb Screw Bakelite Bolt M4 M5 M6
Aliexpress UK
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HIFESON Hand Rivet Nut Gun Part Manual Threaded Rivet Head Replacement Screws Pull Rod For BT-606 605 607 M3 M4 M5 M6 M8 M10 M12
Aliexpress UK
Description: 304 Stainless Steel Material, 0.8mm Thread Pitch, Hex Key Hex Socket, Countersunk Flat Head Bolts Screws, M5 x 30mm. Countersunk bolts is anti-corrosion,rustless,non-pollution and high-hardness. It is widely used in industrial.
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ZONSANTA Metric 304 Stainless Steel Hex Hexagon Nut DIN934 M1 M1.2 M1.4 M1.6 M2 M2.5 M3 M4 M5 M6 M8 M10 M12 M16 M20 Screw Nuts
Aliexpress UK
Description: Stainless steel Material,male thread,silver tone. Machine screw. Feature:countersunk flat head,phillips.
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304 Stainless Steel Hex Hexagon Socket Ultra Thin Low Flat Wafer Allen Head Screw Bolt M2 M2.5 M3 M4 M5 M6 M8 2pcs-80pcs
Aliexpress UK