Hex socket head cap screw P=3(Coarse Steel Zinc plated(Silver) 5 X 12 Pitch 0.8

This is a bolt with a hexagonal socket in a cylindrical head. Tightening is performed using a hex key (Allen wrench).
In most cases, it is used without a nut. It is also known as a cap screw or socket screw.
When fastening a hex bolt, a wrench requires working space, whereas a hex key does not.

Cap Bolt　
Hex Socket Head Cap Screw Encyclopedia
Cap Bolt　P=3

• Hex socket head cap screw P=3 Coarse pitch
• P=3 (With spring washer + JIS flat washer)
• Nominal thread diameter M5
• Length under head (L): 12.0
• Coarse pitch: 0.5
• Head diameter (dk): Nominal 5.5 Max 5.68 Min 5.32
• Head height (k): Nominal 3 Min 2.86
• Hex socket width across flats (s): Nominal 2.5 Max 2.58 Min 2.52
• Hex socket depth (t): Min 1.3
• Flat washer (Dxt): 8x0.5
• Spring washer (d): Max 5.4
• Spring washer (bxt): 1.1x0.7
• Incomplete thread section: Max 2.8
• Partial thread range: L35 and above
• Partial thread thread length: 30-33
• * Full thread thread length = L dimension - incomplete thread section length