Strange lens

Hi to all of you!
I found this lens, and I think it's an Industar pancake lens. But it has no markings on it...what do you think?

http://www.ussrphoto.com/UserContent/252012_ind.jpg

http://www.ussrphoto.com/UserContent/252012_ind.jpg

<blockquote id="quote"><font size="1" face="MS Trebuchet, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by mihai.besliu</i>
<br />I think it's an Industar pancake lens.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Yes. Industar-50-2.

It is for the Zenit.

Thanks to see you here, Jay! And delighted! [:)]

Amitiés. Jacques.

Likewise delighted, Jacques! :)