M2; 0.40mm pitch, 2mm thread diameter 4mm head diameter, 1.3mm head height.
M2.5; 0.45mm pitch, 2.5mm thread diameter 5mm head diameter, 1.5mm head height.
M3; 0.5mm pitch, 3mm thread diameter, 6mm head diameter, 1.8mm head height.
M4; 0.7mm pitch, 4mm thread diameter, 8mm head diameter, 2.4mm head height.
M5; 0.8mm pitch, 5mm thread diameter, 10mm head diameter, 3mm head height.
M6; 1.0mm pitch, 6mm thread diameter, 12mm head diameter, 3.6mm head height.
M8; 1.25mm pitch, 8mm thread diameter, 16mm head diameter, 4.8mm head height.