Use the buzzer to match the pin.Firstly use the clamp of the buzzer to clamp the gold, red and green wire (each 1pcs), and then use the other side of the buzzer to connect it.If it works and sound,measure the lead wire from the bottom cut to 40±2mm.If it can't work,no need to cut the lead wire.After these 3 pcs lead wire all done and meeasure the other 3pcs wire(that clamped) from the bottom and cut to 40 ± 1mm.