JIS Mark 7 Hex Bolts Steel

JIS Mark 7 Bolts Trivalent White Cr-3
Mark 7 Hex Head Bolt
Mark 7 Flanged Hex Bolt
Mark 7 Upset Bolt
Upset bolt
A bolt whose head is formed into a hexagonal or square shape by forging.
Cold-forged hexagonal head upset bolts usually have a recess on the top of the head.
On the market, there are shapes such as 4 mark, 7 mark, cross recessed, and semis.
How to measure
Measure from end of thread to under the head, this includes flat and spring washers

Bolt 6mm Length +0/-1.0mm Thread Pitch 1.00mm Head A/F 10mm 
Flange OD 14mm  Flat Washer OD 13mmx1.00mm Spring Washer OD 11.5mm
Max Head Thickness 4mm-5.4mm

Bolt 8mm  Length +0/-1.0mm Thread Pitch 1.25mm Head A/F 12mm
Flange OD 17.5mm Max Head Thickness 6.9mm-8mm

Bolt 10mm Length +0/-1.0mm Thread Pitch 1.25mm Head A/F 14mm
Max Head Thickness 7mm