everything is WRB..

well..seems also our beloved acoustic/violins are WRB at the end....

The centerply is not hollow though, probably it will make the blade more balanced, other wise it will be handle heavy. Thanks for the info...

@ eecrive : thanks for sharing. did you do on purpose or accidentally broke it :) ?
                  wonder if earlier versions are also semi hollow.
                  of course, if you got older Acoustic or Violin,  you don't need to break the handle just to   prove it

UPROAR!

Where does WRB stand for? 

@ van doorn :
Stiga calls their hollow handle system "WRB", it stands for :

W– Weight balance. The balance of the blade is scientifically moved to the point contact is made with the ball.

R– Rate of recovery. Due to the decrease in blade weight the player improves his rate of recovery after each stroke.

B– Ball sensitivity. The scientifically positioned recess in the handle provides extra sensitivity of touch.

A few questions: How old is this Acoustic?

This is like, the lowest end of WRB I've seen. Which really isn't too bad. I'd say second is the Donic Waldner Senso Carbon and the like, and lastly the full on hollow handles of the Stiga WRB series, including the Ebenholz.

ah i forgot... also butterfly are made like this.

I think JOOLA handles are solid. My blade is head heavy, but makes heavy rubbers like H2 and Thor's feel light.

eecrive wrote: well... Nittaku uses a particular glue... which is easy to remove with a heater... unfortunately that happened during a training session.. now i re-glued the handle without problems....

This particular glue as advertised for the lamina is glutinglue. Glutinglue is heatresistant if not saturated with water. If the griphalves come of by heating (the usual way to remove a griphalve) they are not glued with glutinglue or not glued properly they maybe came of from vibrations.
When a griphalve is glued on with glutinglue (as with Osp blades) it can,t be removed the usual way by heat (approx 90-100 degree) and slicing it off.

There is a simple way to test : if it,s glutinglue the glueremains on the lamina and griphalve should become tacky again when moisted at the surface with a bit of warm water.

The hollow part is for the balance. Otherwise they would have to use less dense lighter wood which can make a thin lamina too flexible and weak in the neckarea. Griphalves on thin lamina,s are also more volume hence they weigh in more.

the new Joola Viva is hollow as well

ejmaster wrote: not everything is wrb. there are blades with 100% solid griphalves and handle.   for instance the dhs hurricane king.

100% correct as I disassembled my HK 655's handle to find that it is a well made handle ,it contains two black pins made of plastic that reinforces the blade handle even more. A solid wooden handle.

The marketing for these blades/rubbers is really incredible...and we are just as incredible for buying into the hype.  Does hollowing out the handle really make that much of a difference!  Am I really gonna swing my racket faster if it weighs a few grams less due to the hollow handle!  I doubt it.  Maybe there is slightly more ball sensitivity, but again....don't think it's really gonna make that big of a difference.  I remember when butterfly tackifire first came out many years ago.  The club that sold it just got a new sheet of it in and while reading the description it said...."produces a frightening amount of spin"...so the guys and I were like woa...I gotta try this so I bought it.  Ha...it wasn't much different than the other butterfly sheet I was playing with.