Can anyone tell me about "decorating tubes"??? I used a decorating bag that was divided in two so you can put two colors in it. Well when I got it out I did not understand how to put the tip down into the bag. Then the instructions said something about these tubes. I was determined to use the bag so I ended up putting the tip in the top and taping it in. I worked, but I would like to know the correct way, beacuse I really liked the efect it made. 
PaulaRuss
ibmoser is correct. Decorating tubes are the same thing as decorating tips. Even some of the older Wilton books refer to them as tubes, instead of tips.
I ran across these directions for how to use the Ateco striper bags today and thought of you:
Description: Use to pipe two different colors through one tube. Fill each half of the bag with the color you desire. Cut end and place in a re-usable bag with a coupler and desired tube already affixed.
Hopefully, that will clear things up for you.
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