I don't tie a skinny "sea habit tube" fly as trey combs does, I tie a "sea habit" on a tube. I'll post instructions when I have more time. Basically the body is small bunch of bucktail, small bunch of flashabou, small bunch of fish hair, repeat until you have the profile you want. Then apply fairly thick shoulders of white bucktail on the side, with some silver crystal flash over it. Now apply some crystal flash over the top, with the grey back I like I use grey ghost crystal flash, some grey fish hair, a little grey bucktail and then some peacock herl. Now just do the head. It's faster than it sounds:rolleyes
A fly that is tied on an 1/8" outside diameter (typically) tube that is either plastic, copper, aluminum...or some kind of tubing. On the hook end there is a piece of soft tubing that the hook slides into, or the hook can be "keyholed" into the hard plastic.
Basically a tube fly allows you to release a fish easier since the tube can be slid out of the way. Change hooks when they dull. Fish hooks other than stainless steel in salt since it doesn't matter because the fly is not tied onto the hook. Just a few benefits.
Other than that it is different...a change...another doo dad to purchase :thumb