What lense should I replace in my mask?

[Dr. Paint]

What lenses will fit in the Vulcan Mask System?

[Easy Target]

Judging from pics I've seen of the Vulcan mask it looks alot like a Spectra mask w/ extra forehead protection. So I'm assuming it uses lenses for the JT Spectra. Heres a pic of the Vulcan for you guys who don't know how it looks like.
http://store4.yimg.com/I/paintballfxcom_1631_1096566