Have you attempted to open the head yet? I tried briefly to open mine up once without success, although I wasn't really trying, if you know what I mean. I believe they use some type of thread locker on the locking ring. If I were you, I would try to find a tool suited for the job (needle nose pliers maybe), and attempt to remove the locking ring first before you spend money on replacement glass that you can't install. I think you can get it open by applying heat with a heat gun, but I recommend you try it first for the previously stated reason, and so you can measure the ID of the bezel or the opening size that the glass has to fit through to get to the bezel. Also, the way this light is designed, it looks like it would be easy to accidentally scar the threading trying to remove the locking ring.
A quick measurement on my TK10 shows that 24.33mm is the ID of the bezel opening at the glass end, so the glass will have to be larger in diameter than that size, but my head isn't opened up, so I can't measure the ID where the glass is. The only options (that I'm aware of) for glass replacement are from Flashlightlens.com. The best option would be the Borofloat lens because it's been said to be more scratch resistant than the UCL lens, but the Borofloat isn't offered in a size that you can use for this light, so we only have two options left. The UCL glass (
click here), or the Hardcoat Acrylic lens (
click here).
The UCL is offered in three sizes that could possibly work for you: 24.7mm x 1.85mm which might be cutting it too close, but that's your call. The next size up is 26.8mm x 1.85mm which would probably be about right, but it could be too small or too large; I'm not sure without having the head open to measure. If it's too large, you might be able to leave the protective paper on the glass and somehow remove material around the OD of the glass to get the required size, if it's too small, they also offer the UCL in a 28.6mm x 1.85mm.
Another option is their Hardcoat Acrylic Lens. It's available in 28.8mm x 1.68mm, and it might be easier to reduce the OD of this lens because it's made of plastic. They claim that it's "abrasion" resistant, but I don't actually have any experience with the Hardcoat Lenses, so I can't comment on durability. Keep us updated on whatever you do. If successfully open the head, some pictures would be really nice if you have time
. We all like to see pictures. Best of luck either way.
Oh yeah, :welcome:
