Yes and they work quite well. I used them once with my G35 sedan when nagivating 8" of snow back in early 2011. We didn't get any snow last year so I couldn't test them out. Here's me in my old RWD G35 driving in about 3 to 4" of unplowed snow, stopping in the middle of a step hill, and then restarting. Not an ounce of spin. Amazing product.
If you're going to run them with summer tires, you should do all four corners. Also keep in mind they're not made for driving on any surface not covered in snow. You'll chew them up in no time so in the end they might not be terribly useful. You can only go 30-35mph with them on too.