Singer have been making machine all over the world for over 160 years, the Same Model machine could have been made in different factories in different countries. that means the same model number could have several different parts.

Dont trust your Model Number!

Always choose your foot control based on pictures showing your socket or lead.

3 pin D Lead fits most Singer Machines

3 pin D lead (larger pins - Singer 530, 830 & 700 series) 

3.5mm Ear phone jack - 

Singer Flat 3 pin socket - One of the most common singer foot controls on the market. 

Banana Lead for very old Singer Machines (Short Supply Left) 401, 403, 404, 221, 222k

5 pin D Lead for old Singer machines, Singer 900, 2000.

T pin for 300k & 400k Machines (singer - 337, 338, 347, 348, 457)

Air Control foot controller

Singer D 4 pin foot control square pattern (600 series)

Singer D 4 pin foot control Diamond pattern (717 & 6704)

Quantum XL Foot Control, Singer Quantum XL1, XL10, XL50, CXL

Sewing machine running on its own 'phantom machine' Singer foot controls; Singer have a wide variety of foot controls as you could imagine from over 160 years of manufacturing sewing machines.