JIS Mark 4 Upset Bolts Trivalent White Cr-3

JIS Mark 4 Upset Bolts Trivalent White Cr-3

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 marks, 7 marks, cross recessed, and semis.
Measure from end of thread to under the head including spring washer

Bolt 6mm Length +0/-1.0mm Thread Pitch  1.00mm Head A/F 10mm 
Spring Washer OD 11.5mm Max Head Thickness 4mm

Bolt 8mm Length +0/-1.0mm Pitch 1.25mm Head A/F 12mm Head Thickness 5.5mm