M5 : Thread diameter 5mm; Thread pitch 0.8mm; Head diameter 12mm; Head height 2.7mm
M6 : Thread diameter 6mm; Thread pitch 1.0mm; Head diameter 15mm; Head height 3.3mm
M8 : Thread diameter 8mm; Thread pitch 1.25mm; Head diameter 20mm; Head height 4.4mm
M10 : Thread diameter 10mm; Thread pitch 1.5mm; Head diameter 25mm; Head height 5.5mm
Bolt lengths do not include the head.