The standard ones just have the one setting.You plug them in.They have a orange light letting you know they are on and are warming.When they get to about 170 degrees it'll go to the green light and standby until it goes below and then kick back to orange keeping them around 170.I have them and they work great.Indy has several differrent brands.Go to Indysuperbikes.com click on home then look for tire warmers and it'll show you all the brands they sell.The digitals are the ones with the settings but the Internal ones work good and will save you some money.Good luck