The Ona Crystal Masturbator is a fiendishly well-designed onahole in a hard cup-style casing for better grip and longer durability. There are three colors to choose from, each with a varying tunnel: the pink is a "tornado" that twists you after a hard dome-like entrance; the clear version is "cyclone" that provides a uniform swirling sensation throughout; and the smoke color version has an "octopus" design that shifts from squares to round bumps and then octopus-like suckers at the end. The toy's cup is transparent, so you can see yourself in action inside. And when you're done, the inner hole can be removed and easily washed.
The Ona Crystal Masturbator features: