Lots of different tire warmers out there that do lots of different things. Some are set at 135 degrees and shut off once in a while to keep them at that temp, some have selectable settings for hotter days, some don't.

The tire sox are cool because they help to keep every part of the tire at that temp (or close to it). No wind blowing through the rim.

The MAIN reason isn't to get them warmed up (although that is a good thing), it's to not have the tires go through too many heat cycles. Too many heat cycles means the tire will get eaten up quicker. No matter how much tread you have there are only so many heat cycles they can safely go through and still be good for track use (at our level).

For track days you don't need 'em. We use them to help with tire preservation and be pre-warmed before hitting the track. You don't have to worry about taking the first lap easy to heat them up; they're already hot!

You can pay anywhere from 270 to over 500 bucks depending on what brand and type you want.