Ahh the sight of a new tube. Makes me all happy inside 
Opted for the one sold by LightObject. Could have saved some money from another vendor but LOs tubes come prewired and are tested at time of shipping. Also the tube construction looks very professional and high quality.
Please do a follow-up post on how it performs once you have it installed!
Will do!
If you were to guess, how many hours do you think you got out of the original k40 tube? Did it die a slow death or did it just tank?
Not sure on hours. I’ve had my laser for just over 2 years now. I would classify my use overall as moderate with some heavy production runs in that time. A few months ago I noted that the tube was drifting into a higher TM mode and I was getting much less power. It still works fine for 1/8" material, just have to cut a bit slower and at higher power. It now really struggles to cut 1/4" ply even in 2 passes. Even then I’m going so slow it results in lots of charing. Decided it was time and I’m going to do a bunch of other upgrades at the same time.
SPTs are good stuff. I tried to join the laser product resell market, but light objects owns it. They are a good company with good products. I still use SPT products in my laser CNCs and they make products that can compete with the name brands out of the same region great choice @Nedman
@donkjr Lol. Well since it does still have a bit of life left in it, I was planning to hang on to it as an emergency back up. Why do you ask?
@Nedman I have some tests on my list to characterize the water conductivity and need a test setup with a laser and its water jacket. The laser does not have to work.
Then again it may take me some time to get to it. I figured if you were trashing it I would ask :).
I have a long list of stuff waiting in the shop. 
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