Take a look at the "Performance" section of my review for the small one. It talks about how to use it.

I think it's a nice item, but the manufacturer dropped the ball by not including directions.

I saw your question and answered it in the comments, but I'll add it here as well.

The "insertable portion" is smaller than the length of the wand for two reasons:

1. To work your Kegels, you use the end of the exerciser with the bulges, but they only cover just over half of the total length (roughly 4 inches).

2. For pleasure purposes, you can use either end, and go a little deeper, but for safety (especially if used anally) you should maintain a firm grip on it. When your hand is wrapped around the "handle," you'll only be able to insert part of the toy — about 4, maybe 5 inches.