Bob DeVoe made these hollowing tools in his machine shop in several sizes - this is the next to the largest size and has a 5/8 (.625") shank, to hold a 3/16 inch square or round tool bit - it comes with a square bit, the proper sized allen wrench for to change out the bit, and a sharpening fixture (with wrench), a brass ferrule and spare hex setscrews.  

He felt strongly that woodturners should be able to make their own handles, so he didn't provide handles with any of his tools for many years, in his last couple of years he bought inexpensive handles to go with the tools - This one has a handle a friend made for him.  I have one which I use for rough hollowing where a gouge doesn't work well - I have a 24 inch heavy handle on mine with a piece of brass tubing for a ferrule to keep it from splitting (the handle on this one is 18 inches).  

I prefer this HSS to the carbide tipped tools because the HSS bit is easy to resharpen, cheap to replace and does not chip like carbide does if there is a shock load.  You can also get HSS a lot sharper than carbide so you can get a better finish if you are using this in a near-finishing operation.  You can use 3/16" brazed carbide bits if you want to use carbide for highly abraisive woods, and they are cheap also.

you are buying the item shown (tool, wrench, bit, sharpening fixture with wrench)  If you want to do machining I have some partly completed tools that I'm considering raw material right now, contact me if you want to take them on and complete them.  I also have some more sharpening fixtures in this and other styles from my friend's estate.