15 watt reverse HIDs: Would not recommend these. I used for JohnDeere lawn tractor headlamps. They are bright enough, but I believe the ballasts to be the DC type which are notorious for unstable arc and color temperature shift, as mine do. The ballasts have poor wire strain relief grommets which allow the wires to twist more than 360 degrees possibly causing a short condition. You're better off buying a 35W kit of higher quality for the same money, and make bulb holder mods to accept T25 bulb.