I run at ardent racing ( biggest indoor track in the uk ) google it.
I used to race a mi4 made bye the same company as those tyre warmers.
I have never needed them for indoor carpet but if you do go outdoors and it's cold, youl need em
. Don't use these for foams though. oh and if you need somewhere to race pop down to ardent raceway because there's loads of people down to help you
