It has Several Sizes teardrop for retention and then several sizes shaft for the rest of the way to a 5 mm flat disc to prevent it from being inserted too far. All hollow for fluids to flow through. Amazing for all-day wear. Take control of your own pleasure with the Silicone Teardrop Penis Plug and relish every intensely pleasurable second that it occupies your body bringing you closer to the orgasmic release you crave!