I'M WANTING TO BUILD A WTC. I HAVE NOTICED THAT ON ALL THE WTC I'VE SEEN, THERE IS A BRASS ROD HOLDING THE PUSHRODS IN PLACE. WHAT IS THE SEAL TO KEEP WATER OUT? CAN SOMEONE PLEASE GIVE A DETAILED DISCRIPTION OF HOW THESE SEALS WORK?.....ALSO.....WHAT IS THE COMMON OPINION OF THE DUBRO PUSHROD SEALS AS A SUBSTITUTE?

THANKS
CHRIS