Strictly speaking the term male vibrator doesn't make a lot of sense. Vibrators aren't made for people or genders as much as they are made for specific body parts or specific sexual activities. You might think that a male vibrator would be any vibrator that fits on, or over, the penis. And it's true that people who call themselves male (or men) might love a vibrator like that. But there are lots of other vibrators that don't get used on the penis that men enjoy and could rightly be called male vibrators. The way marketing (and gender binaries) work often means that we have fewer options, and when it comes to sexuality that's not ideal. So the best way to think about male vibrators are that they are any kind of vibrator that's being used by someone who calls themselves male.
With that qualification in mind there are three main kinds of male vibrators. There are vibrators that are designed to fit around the penis, called vibrating rings. These shouldn't be confused with penis rings, as they don't usually function the same way.
There are also vibrating penis sleeves which usually cover the entire penis or are hollow sleeves that the penis is inserted in.
And finally there are male vibrators that are meant to be inserted anally, also called anal vibrators. Again, you can see how these categories aren't perfect as women can also use anal vibrators. And there are those who don't feel like the words male or female always apply, but can still completely enjoy vibrators.
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