The M3 specifications are as follows:
Ball head buckle size: M3 × Φ3 × D10.5 × d6 × L30mm
Ball head buckle bottom hole diameter: 3mm for M3 drawbar wire
Rolling metal ball aperture: 3.0mm metal ball diameter: 6.0mm
Round ball head diameter of the top of the joint: 10.5mm Total length of the ball head buckle: 30mm