Does anyone anyone sell a lid or a cap for the eGo Twist batteries? I carry a spare eGo Twist in my pocket to replace the one on my PV when it's charge runs out. The connection end of the battery tends to accumulate fuzz and dirt. I'd like to get a screw on cap to keep it clean. I could probably glue a lid onto any of the numerous adapters out there, but if someone sells a cap specifically made for this I'll take a few.