Zippers come in three basic systems; there are the spiral type (also known as coil zippers), the injection molded profile type (also know as delrin or Vislon for the name of the injected material) and metal (usually identified by the material used; eg. aluminum or brass.)

#1 Coil Zippers use the toothed elements of helical coils of polyester, nylon or in some cases metal wire as the fastening system.The opposing elements of the exposed coil interlock with each other to  form the closure. The coils can be formed and woven directly into the supporting tapes or pre-formed and sewn onto specially pre-manufactured tapes in a separate operation. These products are
widely used because of their inconspicuous appearance when incorporated into the finished product. The nylon and polyester coils will not generally break an industrial sewing machine needle if stitched over, which allows bar tacking as a method to close one end of  the fastener.


#2 Injection Molded Zippers manufactured from Delrin or Vislon compounds have a larger bulk than coil zippers. These zippers have teeth of individually coupling members that interlock and are injection molded onto a pre-woven dyed tape. They have a degree of self lubrication and tend to be somewhat sturdier than an equivalent size of coil zipper. They also handle water and impurities better than coil zippers and in the larger sizes are the ideal choice for outdoor topping applications such as boats and other marine fitting applications.


#3 Metal Zippers have teeth of stamped or diecast interlocking design fastened to the beaded edge of a dyed supporting tape. They have a long life and tend to be very sturdy and strong in all directions. Brass zippers are used in Marine applications as they do not rust as much as steel. They are also used in Applications such as garment and upholstering due to the desirable brass or metal finish.


Zippers are available in running yardage or cut length finished products. The finished zippers are separable like those found in jackets and other garments. The running length system allows zippers to be made up to the length required. Where needed, there are top and bottom stops available along with the sliders for the zipper tape.

Which zipper should you use? It obviously depends on your requirements. If strength is not a particular concern, go with whichever zipper will give you the finished appearance you want. Hidden and low profile would lead you to the coil style. If you wanted a more traditional look for a leather garment you might want a larger brass finish zipper on black tape. If strength is an issue, select the largest size that  would fit the project. Metal and Delrin are stronger, although the larger coil zippers are strong enough for bags and other applications. Clamp-on zipper securely hold the slider for the insertion of the tape, and can be a real time saver if you are trying to move large volumes of zipper through a production line.

Pre-Finished zippers are available in a large assortment of lengths in both auto-locking or non-locking styles. Coil zipper sliders are available in locking and non-locking sliders. The locking sliders have a small tooth on the bottom of the tab that will lock into the teeth of the chain and prevent the slider from further movement until the tab is lifted.

YKK's PREMIUM LINE
YKK Vislon zipper is is extremely strong and lightweight. The "teeth" are made from Vislon nylon and the tape is polyester. Due to the
unique properties of Vislon, the fastener has a wide variety of industrial, consumer and military applications where environmental conditions
can reduce the effectiveness of metal zippers. It is corrosion resistant. The zipper is self lubricating  to a degree and operates smoothly despite
sand, mud or other contaminants. The colour is cast into the molding, so there is no finish to rub off, peel or chip. Vislon has excellent heat
resistance (up to 360° F/ 182°C) and resistance to cold (down to -60°F/ -51°C). It melts at 480° F/ 249°C, which is well beyond normal
laundering or exposure temperatures. Resistance to chemicals further extends the use of Vislon beyond the scope of conventional metal zippers
which are prone to accerated corrosion with exposure to chemicals. Vislon is a consistent quality product from YKK.

What does the number with the zipper represent? ie. #4 or a #10
The number listed with each zipper is the size of the "teeth", generally the larger the number the larger the teeth.

A word of caution when buying sliders, stops, etc. for your zipper. It is recommended that when purchasing a specific brand of zipper that you purchase the identical brand of slider. This is due to the fact that the sizing may not be an exact match. So if you buy a YKK brand of zipper, you should purchase the YKK sliders. Otherwise you may have problems getting the slider on or you may experience premature wear.