Interesting knuck cylinders on ebay

Hi all-

I happened to catch this yesterday on ebay right before it closed. Some knucklehead cylinders that went for big bucks.

http://cgi.ebay.com/ebaymotors/ws/eBayI ... K:MEWAX:IT

They certainly appear to be different than the ones usually seen - at least the ones I've seen in my very limited experience. Does anyone know anything about them? My only real reference is Palmers book and there is no mention of them that I could find. I'm just curious.

4 fin 61" cylinders with early casting marks. Rare and desirable!
Robbie

Robbie,
Can you decipher those early date codes? 11-12 and 11-24 make no sense to me.

Can you decipher those early date codes? 11-12 and 11-24 make no sense to me.

Chris,
I wish I could but without inspecting those cylinders to see what else may be on them, no.
Robbie

Can you decipher those early date codes? 11-12 and 11-24 make no sense to me.

Chris,
I wish I could but without inspecting those cylinders to see what else may be on them, no.
Robbie

What else do you need to see? I have several of them.