Review on Dsycar 6 Pack Gold Metal Valve Stem Extenders - 45°, 90°, 135° - Universal Extensions for Car, Motorcycle, Bike, and Truck by Hector Smith

They are expensive but seem to work well. They loosened and my tires lost all air. I have a twin truck and bought these for my external duals because the valve stems face in. You can usually use truck tire tools to check pressure and add air, but my hubcaps made it difficult. I tightened them as tight as I could for fear they might come loose. After about 600 miles (I know because I was on vacation with our RV) we hit dirt roads and both valve stem extensions came loose. Both external duals failed completely, leaving us in a bind. In another application or maybe some Loctite they might work just fine.