You want just the center? For the HT? Best source is from Bimare.
or you can replace them. IF you do, go to West marine and get new Beckson, you'll need to replace the ring and the cover, because the threads are differient, the Beckson ones are a great improvement, they dont leak and they dont get frozen shut with fine grained sand like the original ones do.
Plus if you ever lose one, its an easy replacement from Beckson, the ones that came stock on the HT are harder to get, I've only been able to get them from Bimare.
www.beckson.com They have overstocks and special on the web site.
These would work, for $4
http://www.beckson.com/Merchant2/me...mp;Store_Code=B&Product_Code=166Bill
