There are currently no internal green lasers. Crimson Trace (laser grips) is still totally red and so is Lasermax, the maker of the famous internal guide-rod laser. I'm praying the day will come soon but right now it hasn't made it to market. The smallest available green laser is the Lasermax "Unimax," a smallish rail mounted unit.

I've seen some green and red ones that mount to a rail under the bbl. but most of them I have sen were brands I have no idea who made them and if they were any good. eBay has tons of them. My wife bought me a red one of the type a while back. I don't much like them on my weapons but I did play wit hit for a while. I liked to drive my cats nuts shining it all over the house (it wasn't on a gun when I did this).

It did seem to work for a pretty long time before the batteries went dead. An I had found the batteries at a local jeweler. I'm sure Walmart has them too. Like I said I'm not sure how good they are being I did not have a quality one to compare it to. It went a pretty long way. I shot the beam out the back door to one of the barns here that's about 60-70 yards away and it was easy to see in the dusk light at the end of the day. I guess that's pretty good.

I think "Viridian" makes internal green laser sights. Think you have to have a shop install it or the company; check out the website and let me know what you think?