This is a 20" A Zildjian Swish cymbal with 6 rivets. The swish cymbal has a long history in the jazz world as being the cymbal that every big band player must have. I have wanted one of these for a long time and couldn't stop myself from buying this one when it came up.
I have had 2 swish cymbal besides this one and got rid of both. The first I returned to the factory because it had cracks where the rivets were drilled and frankly, it sounded terrible. The other was a beautiful 22" Bosphorus which I still can't believe I let go. (Long story) This Zildjian is certainly no replacement for that Bosphorus but it sounds great. It has a complex, articulate ride sound with just enough sizzle.
I'm not entirely sure about the history, but it seems that swish cymbals came with 6 rivets until the 1980s when they were bumped up to a beefier 22" with 20 rivets. I like the 6 rivets over the 20 as that many rivets can be hard to control. This cymbal had 3 original rivets when I bought it but they were steel and had rusted. I replaced all the rivets with some brass Bosphorus split rivets which are lighter and have a more musical sound to my ear. I can't wait to take this cymbal on my next gig and see how it performs with a tenor saxophone.