A few years ago I purchased a pvs-14 kit, and a separate mx-11769 tube and assembled a pvs-14. The lens from that kit is in the middle of the photo below
I am building a pair of binos and have been getting together tubes and optics, I finally got the objective lenses. One is nearly the same as my previous lens (left), the other is longer (right)



All three lenses work great and I can find no difference between them, but I'm a bit worried about the long one. Fully seated in the pvs-14 obstructs the tube


When focused it's farther out, like this. But I can feel it butt up against the tube while focusing


So what's the deal with the oddball lens? Do I need a special spacer or something. I can only verify pvs-14 compatibility. But am planning on building a mod-3, and I don't know how it will work in there. My plan is to use the oddball in the pvs-14, and the two matching ones in the mod-3. As I stated, I am a bit worried about it seeming to make contact with the tube though, and it's definitely longer than the other ones

Can anyone drop some knowledge on me?

Also, who has the best deal on a variable gain mod-3 including a cleaning/purge?

i think the longer one will be for the pvs7 goggle

My vote is to buy a matched pair of objective lenses and sell the old ones. You'll beat most of the hassle and have a matched set.

Yup, most likely a PVS-7B lens which does fit the PVS-14 body, but doesn't function 100% correctly (bumps into tube as you stated).  They get sold off as PVS-14 lens because they look so similar.  Particularly when not in the PVS-7 front lens housing.  I have made the same mistake in the past.

Longer one is for a PVS-7 as said above.

^^^^^^

Good to know, thanks guys