There are three internal components for the  Z-Vibe and Z-Grabber - a heavy spring, a Vibe Battery, and a motor/spring assembly.  

To assemble:

1.  Put the motor into the handle first (spring end last) 

2.  Then the battery (as shown in the image below)

3.  Then the heavy spring 

4.  And finally the Switch Tip (the tip that matches the handle of your Z-Vibe / Z-Grabber and that you twist to turn it on).

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This order can also be reversed:  in the picture above, imagine the arrow is pointing to the left instead, and put them into the handle spring first, battery next, and finally the motor (in the same order as pictured though).  As long as the parts make contact with each other in the order as pictured above, they'll vibrate. .

Vibration will always be slightly greater on the end that contains the motor, so although the motor only has one speed, you can play with the intensity by how it's assembled.  If you assemble it in the direction of the arrow as pictured, vibration will be greater towards the Probe Tip end of the handle.  If you assemble it in the opposite direction, vibration will be greater towards the Switch Tip end.

To turn the unit on, twist the tip into the handle just until it starts to vibrate. Any further will not increase the vibration, but significant over tightening (although hard to do), may damage the motor.

All spare parts for the Z-Vibe and Z-Grabber are also available separately here.

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