Always tighten your dust cap connector with your finger. No tool should ever be needed to get one of these caps off. It’s best not to use any kind of tool to tighten them. If you screw your valve stem caps on too tightly, you could damage your valve stem. Put the valve stem cap on the valve and turn it a half turn in the opposite direction of the clock. This will help make sure that the cap is properly seeded along the threads of the stem. Then, carefully turn the cap on the stem in a clockwise direction. When the threads catch, the cap will start to get tighter. Keep turning the cap with your fingers until it fits tightly at the bottom of the threads on the stem.