Countersunk flat head square neck bolt also called plow bolt.

Countersunk bolts are used when a smooth surface is required. 

Size: M6/M8/M10

Length: as per size

Thread type: metric corse right-handed thread

Thread length: partial thread

Material: steel

Grade: 4.8/6.8/8.8/10.9/12.9

Finish: plain/black oxided/zinc plated/hot dip galvanized (HDG)

Technical info: DIN 605