Quick Change Tool

What Is A Coupler?
The coupler is the "quick-change" tool for decorators. It allows you to change between decorating tips easily and without changing out pastry bags. It's a little 2-part device which attaches to the end of the pastry bag. The base fits inside the bag. The decorating tip goes on the end of that (the portion of the coupler that sticks out), and then you screw the ring around the tip to secure it in place.
When do I need one?
A coupler is really helpful for fast changes to your decorating tips and tubes. For example, if you are using one color icing and different style tips, you can use a coupler to easily switch between tips, such as a star tip and a star-burst tip.
Using a coupler allows you to change the decorating tip without changing the pastry bag.
Do I always need one?
No, if you are using different colors of icing, it would be easier to have different pastry bags, so no coupler is needed. Just drop the tip into the bottom of the bag.
DON'T Throw away the coupler! Remember if you use a coupler in a disposable pastry bag to remove it before you toss it.  Just snip the pastry bag at the wide end of the coupler and pop into the sink.
QUICK NOTE: Fat Daddio's standard couplers fit all standard pastry tips. 
HELP! It doesn't fit in my pastry bag!
Yep, sometimes when you use the medium or larger tubes the coupler doesn't come to the bottom of the pastry bag. So you have to cut it. What! Cut my new bag?! Yep, but here's how Trim Your Pastry Bag
What about the tubes?
These larger tips (or tubes) do not have couplers. These were designed for piping cream puffs, mashed potatoes and larger uses. You more than likely won't change the color on those potatoes.
For more inspiration, visit our Frosted Pinterest board.