Hex socket head cap screw(GOSHO(Gosei(Coarse Steel Unplated 6 X 20 Pitch 1.0

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This is a bolt with a cylindrical head featuring a hexagonal socket.
Tightening is performed using a hex key (Allen wrench). Although classified as a bolt, it is in most cases used without a nut.
It is also referred to as a cap screw or socket screw.
Spanners and wrenches with jaws for tightening hex bolts require clearance space around the work area, whereas a hex key requires no such space.
For this reason, the use of hex socket head cap screws allows work in confined spaces and enables more compact machine designs.
Due to their appearance, they are also increasingly being used for decorative purposes.

• Hex socket head cap screw Gosei Gosei Coarse pitch
• Nominal diameter M6
• Length under head (ℓ) 20.0
• Pitch 1.0
• Thread section (b) Reference 24
• Head diameter (dk) Max 10.22 Min 9.78
• Neck diameter (da) Max 6.8
• Body diameter (ds) Max 6 Min 5.82
• Head height (k) Max 6 Min 5.70
• Neck fillet (r) Min 0.25
• Hex socket width across flats (s) Nominal 5 Max 5.14 Min 5.02
• Hex socket depth (t) Min 3
• Head chamfer (v) Max 0.6
• Full thread range 30
• Strength class 12.9(M2~M20) 10.9(M22~M24) 10.9(Electro zinc plating)