The plastic material of the Gyrating Hummer has a satiny smooth finish, and becomes very slick once moistened. This really seems to help transmit the vibrations.
The only problem with this toy's material we have found is that it's made out of plastic and only rates an 8 on the Eden Safety scale.
Here's a link to the specific info on the material safety scale: http://www.edenfantasys.com/sex-guides-and-tips/guides/materials/plastic
The head of the Gyrating Hummer has a depressed section on one side of the head that is designed to cup the clit for maximum stimulation of the whole clit. On the other side of the head is a small nub which I believe is designed for focusing all of the vibrations on a very small area. The nub is roughly the size of a pencil eraser.
The one design issue we had with this vibrator is that it took us a bit to figure out that holding the control button on the base of the toy down for a few seconds turned it off. Once we figured that out, and that turning it back on brings you back to the same vibration setting, we were a lot happier.
The Gyrating Hummer is a fairly powerful vibrator, considering it is only powered by a pair of AA batteries. There vibration intensity and pattern is controlled by a single button on the bottom of the toy, which is used to cycle through the patterns. My wife highly recommends taking them all for a test drive.
Here are the vibration intensities
1. Low power
2. Medium power
3. High power
These are the patterns after the 3 solid vibration speeds.
4. Medium throbbing
5. Alternating short and long throbs
6. Two short throbs then a long throb
7. Rising and falling intensity of vibration
8. Short throbbing then the rising and falling intensity
9. Short throbbing then a high intensity vibration dropping to lower.
10. Stronger throbbing following by the rising and falling intensity.
(Basically #8 with a stronger first throb)
The plastic material covering this toy uses, plus being waterproof, makes it fairly easy to take care of using soap & water plus a disinfecting toy cleaner or wipe. Unfortunately, it's not as easy to sanitize as silicone, but the material does make it safe for any type of lube.