What size thread on the HD chimney brush rods?

Do they use the 1/4" or the 3/8" threads on the typical black fibreglass chimney rods at home depot? I want to order a brush. I think its quite large so I'd go for the 3/8 but I don't reallt remember (I'm at work now so I can't check).
I presume I need an 11x11" brush for a chimney that size? No need to go any larger is there?
Thanks!
Dean
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given those choices, they must be NPT. And they are typically 1/4".

WHAT "that size"??? If your flue is an 11x11 then that's the size you need. If it is a 8" round, then THAT is the size you need.

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On Mon, 17 Sep 2007 08:02:43 -0700, dean wrote:

Do you have any nuts or bolts you could try on for size? Taking unit to hardware store should help you find the right size thread.
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