To properly install an invisible zipper, you must have an Invisible Zipper Foot. As the zipper coils are guided through the tunnel system, the needle sews as close the coils as possible.
#35 Invisible Zipper Foot, Bernina
Husqvarna VIKING sewing machine accessories - HUSQVARNA VIKING®
6MM Open Toe Foot for Pfaff Sewing Machine - Ireland
Snap on Invisible Concealed Zipper Footsingerjanomebrother
Huskystar 215
Clear Invisible Zipper Foot for Husqvarna Viking Sewing Machines Emerald 116, 118, 122, 203, 183, Lily 555, 550, 545, 540, 535, 530 and More
Invisible Zipper Foot
Fits Viking HuskyStar H|Class Series Models 207, 215, 219/224, E10, E20, C10, C20, 100Q, Husky 140, 145, Group A Models : Type A 219-224. Refined
Concealed Invisible Zipper Foot With Guide for Viking HuskyStar Sewing Machine
Tutorial: Installing an Invisible Zipper (with video)
Good quality ready-to-wear garments will often have an invisible zipper fitted. These zippers are often neglected by the home dressmaker which is a pity because the Concealed Zipper foot can ensure success everytime. Invisible zippers are suitable for all fabrics from fine silk jersey through to suit weight wools and tweeds. The key is to get the needle as close the fastener as possible, which this foot accomplishes by slightly unrolling the zipper just before the needle.
Janome 1600 Series Concealed Zipper Foot 767410016