Can yo tell me what this is for? and should I buy one if I can?
Thank you,

Sheila,
A hairspring vibrating tool is used to fit a new hairspring into a watch. The new spring, which is much longer than needed, is fitted to the old balance, and "pinned " at a trial location toward the outer end, where the watchmaker estimates the correct length of the new spring to be. The height of the balance/new spring is adjusted so that the lower balance pivot is lightly touching the glass cover. There is a master balance carefully calibrated to vibrate at 18,000 beats/hour, mounted under the glass in the base of the tool. Both balances are rotated an equal number of degrees from the rest position, and released simultaneously. The watchmaker observes both balances to see if the trial spring balance oscillates slower or faster than the master balance. The trial pinning position is then adjusted to make the balance run faster or slower as needed and the process is repeated until the two balances rotate together at the same (18,000 beats/hour) rate. The new spring is then cut to length so that the correct "pinning" position will fall between the two index pins when the regulator is in the middle of its fast/slow range.
If you want to own a vibrating tool because it is a beautiful piece of well made and finished machinery, go for it, but it is unlikely than anyone but a very skilled watchmaker would ever use it for its intended purpose.

Hi Ed,
That's exactly what I wanted to know.
Thank you!
Sounds very confusing, but I actually understood what you said. Although I knew that it was a piece for a REAL Pro, I thought it would be a nice piece for collecting.
Since it is used in the process of watch "Fixin" I think I may consider it.
I love all things "WATCHES"
I can now keep your explanation with it, if I decide to purchase it.
Thanks again,

Sheila,

This vibrator has the look of being shop made. There is nothing inherently wrong with shop made tools but they certainly don’t command the same price as their brand name counter parts.

Good luck on buying it.