what is this lens??

hi everyone,
I've just seen this posting for a mamiya C2. Can someone tell me what this lens is equivalent to? i don't quite understand..im new to the TLR world. It's listed as Mamiya-Sekor 1:2.8 f=8. 0cm lens. Also i notice that the mamiya flex logo is nowhere to be seen so im wondering if it's a different viewfinder? Im considering buying this thing so i wanted some advice....

Seems to be a mistake on the seller's part. The lens is likely an 8cm (80mm) f/2.8. That's a normal focal length for a 6x6 negative - akin to a 50mm lens on 35mm film.
It also looks like a Mamiya C22 to me. The nameplate is going to be behind the hastily-applied leatherette on the front of the camera.

ah i see. Ok i tried to zoom in on it on the lens and it says 8cm, so i think this makes sense. Any idea what that leatherette thing is there for? haha

Probably a holdover from a time when Japanese cameras were seen as less desirable than European cameras (i.e. Rollei) - but that's just a guess.

One of the two different 80mm f/2.8 Chrome series lenses for the earlier Mamiiya TLRs.
See Graham Patterson's excellent resource here: http://gapatterson.org/mfaq.html
What is the fastest shutter speed? The answer to that question will tell you which version it is.
An 80mm/8.0 cm lens is a "standard" lens for a 6x6 TLR.