M4 x 0.7mm Pitch. Manufactured from solid brass, not brass plated. All screws are fully threaded.
Solid Brass Screw Slotted ROUND Head Wood Screws 2mm - 4mm #2, #3, #4 #6 #8
SOLID BRASS COUNTERSUNK RIVETS 3MM 4MM DIN661
SOLID BRASS METRIC COTTER SPLIT PINS 1.6MM 2MM 3.2MM 4MM 5MM 6.3MM
Solid Brass Screw Slotted Raised Head Wood Screws 3mm, 3.5mm, 4mm #4, #6, #8
M4 4mm Brass Socket Head Cap Screw DIN 912 Allen Bolts Hex Drive 6mm-40mm Long