Manufactured from solid brass, not brass plated.
M3x0.5mm pitch; head diameter 6mm; head depth 1.8mm.
M4x0.7mm pitch; head diameter 8mm; head depth 2.4mm.
M5x0.8mm pitch; head diameter 10mm; head depth 3mm.
M6x1.0mm pitch; head diameter 12mm; head depth 3.6mm.