What chain is this?

[livemusic]

The dealer told me that the previous owner I bought this Stihl ms-290 from had put a bar on it that the saw is not designed for -- 20". I'm not sure that's right but that it is the maximum? I think he also said that the chain was maximum cutting power or something along the lines of that. He said it would work but don't push it. New to chainsaws for the most part, and there is quite a bit to learning about a saw. What is this chain type, let me know if it is indicative of anything I need to know, lol. This is what he sold me when I told him I wanted an extra chain. I think he remarked that it is identical to what is on my saw.

The replacement chain box says:
Stihl Oilomatic
3623 005 0072
20"
72
3/8"
33 RS 72
.050"
Rapid Super

What does all of that mean? I understand that 20" and the 72 and the 3/8" and the .050" designations. Is this a 'safety' chain? Is it 'chisel' or max cutting power or whatever you call that? It has a link that is colored but I can't tell if it is yellow or green! I could call it either one, lol.

The chain that came on it when I bought it used (new 20" bar and chain) has "c1" marked on some of the cutters. What does that mean? (I do not see a colored link on this chain.)

Thanks.

 

[JonCraig]

At first I thought you were singing a Christmas carol. Go ahead… sing it in your head.

 

[KenJax Tree]

That is non-safety chisel chain. The link on Stihl safety chain is green and the non-safety chain link is yellow.

I think the C1 is a Carlton chisel chain.

 

[livemusic]

That is non-safety chisel chain. The link on Stihl safety chain is green and the non-safety chain link is yellow....

Without seeing that it's green or yellow, how do you know that? What, in the nomenclature, tips you off to that? (I guess the link looks more green than yellow, but it's kinda hard to tell.)

Also, what does 'rapid super' mean?

 

[CR888]

Its full size 3/8 pitch full chisel 050 gauge 72 drive link Pro yellow chain. Good choice!

 

[KenJax Tree]

33RS72 says its non-safety chisel chain. If it was safety chisel chain it would 33RS372.

Stihl uses a 3 to designate safety chain.