After all the problems with down and lock retracts, I have went back to the eflite gear on the light jets and they work great. They are very cheap and very fast. Thanks for the advice. I never had to put rf filter on eflite gear and they work with everyones door sequincers. Troybuilt models also have gear conversion I am switching to, have not tried them yet. But troybuilt gear is less than 100 buck for a complete set. You can do 5 airplanes for the price of oneof down and locks stuff.