I stock Invisible Zippers in 3 weights:
#2 or 2mm: Stocked only as finished or complete zippers (the heads are too hard to put on)
#3 or #4: Medium weight (3.6mm across the closed coil) as yardage or completed zippers.
#5 or #6: Heavy Duty Weight (5.6mm across the closed coil) stocked as both yardage/heads & finished zippers.
If you have #3 Invisible Heads from another manufacturer, they will fit my #3 or #4 invisible yardage.
#5 Invisible Heads will fit my #5 or #6 invisible yardage.
If you can't put the Invisible Heads on, select "Heads on Tape" & we will put the head on your tape for you.
Here is a video to help you put the pulls on or go to "Videos" for my youtube channel.