Instruction: Evaluate the answerability of a question by analyzing the related document, outputting yes if the document contains information addressing the question, and no otherwise.

Input:
Question: Will it fit a tool that is 1/4" in size?
Document: In the case of these larger 1/4" shanks, a collet setup would be better than the three jaw chuck to save weight and keep the size down.There just might be a Dremel hand piece with collets one day as it is shown in the owners manual.Good news is that Dremel has made the hand piece a standard size fit and not proprietary "Dremel" fit.
It is very easy to control this tool precisely.The other aspect of the tool I really liked is the chuck keyed tool tip. My other engraver/grinder has a hand tighten chuck with a brass insert based on the shaft size of the tool being used. With the Fortiflex, there is just the chuck with a chuck key to suit all sizes of tool bit.
The chuck is quite tiny and opens enough to accommodate the usual size rotary tool stems.To control the variable speed of the motor you get a foot pedal in between the motor and the wall socket which works very well and offers very precise variable speed control with more precise control since you have both hands completely free to handle the work. The foot pedal feels somewhat low quality though; the plastic is light-weight and has a lot of give in it.
If you are like me you were constantly shifting the typical hand held rotary tool in your hand after extended use trying to get a comfortable grip, sometimes even switching hands. I know some have said the Forti-Flex is heavy but I actually found, because of the smaller size, that when properly hung I was getting less hand fatigue than my hand held. I found the best spot to hang it was just off my right shoulder and slightly back.
Dremel 9100-21 Fortiflex Heavy Duty Flex Shaft ToolThe New Dremel Fortiflex is the ideal rotary tool for people engaged in creative and detailed projects that require precision and versatility combined with power and speed. The Fortiflex offers a reliable and high-performance solution at a good value. This tool features a powerful 2.5-Amp (1/5 HP) Motor provides high torque at low speeds.Its flexible shaft includes a patented bearing system for durability and cool operation.
It has more of the feel of a pencil in your hand, and it allows much more accurate cutting, grinding, and carving.The second advantage of the detached motor is that it allows a more powerful motor, since the weight and size of the motor is not longer an issue, since you are not having to hold it during operation.
It is lightly sprung but still firm under foot for precise control. Still,  I will keep you updated on how it holds up over time.In use, the Fortiflex feels good in the hand and has more torque than my regular-corded Dremel rotary tools (4000 and 4200) and the chuck takes all the same small accessories. (There is support for collets but not in this kit.) The manual mentions a collet nut that fastens to the chuck and holds the various size collets.
The included accessories give a basic array of the types, including carving, engraving, and sanding. Overall, I am incredibly happy with this tool.
for example;Vermont American 14929 Chuck Key HolderAll of my "wishes" are really for the next version and do not by any means mean this is not a great tool because it is and should last a long time after the 2 year warranty expires.
Beyond the headpiece, the cable is thicker and pulls a fair amount.My only reservation would be that if you plan to do precision work for a long period you should either have a strong hand and firm grip or possibly consider a different tool.
Answer: yes