30.78mm diameter. I don’t know how to identify pitch. I also think there is only one extension for both models.
Edit: I see what you mean about different models now that I look at the listing. Mine is the M3-c extension.
Thank you for actually measuring the diameter. That would be 31 mm nominal.
However, I’m quite descriptive in recognizing thread form. As for the pitch, it should be 1.5mm so 2 full threads equate to 3mm. If 1.75mm then 4 full threads equates to 7mm.
BTW, I’m looking into extending a build, not a Convoy light.
Don’t want to undermine your measurement, but in your first response, you gave a 30.76mm diameter. This is what I expected as most 26650 tubes use a 31mm thread diameter (not confined to Convoy’s there).
But 32mm could also have been designed to allow for the added depth of the square thread form.
Edit:
An easier way to measure pitch – place a small (metric in this case) ruler against the threaded part and count how many full threads line up to any of the ruler’s scribes. Somewhat to measuring with an old-fashioned vernier calliper. So a 2mm pitch would repeat itself every second ruler marking. A 1.75mm pitch repeats at 7mm intervals (7mm ÷ 4 threads = 1.75mm).
Came here to say this. As far as I can tell they are all exactly the same. Heck, in the product photo, L7 has a “Silver for M3-C” extension installed. I also know a guy who has the “Gold for M3-C” extension installed on his L7. It seems to me that there is no difference.
Also, the extension tubes may physically fit on the head end of L7’s tube but you have to remove the anodizing from the front threads of the extension tube if you want a reliable connection.
Simon pointed that the silver/gold for the M3s, the red/purple for the L6/L7, and this in my messaging him.
And the product page description doesn’t match the picture. Confusing.
As a female square thread will accept a trapezoidal male thread, it’s not to say these are the same. There is some but not all interconnectivity. Simon would’ve clearly marked they were compatible with one or another.
Unless you have the said extensions in your hand, I wouldn’t claim they are the same. I just so pointed out how to distinguish between the types of threads and it seems no one really looks at this.
I have 4 silver, 2 gold and 1 red extension. I have the L7, L6, M3 and the M3-C. All extensions I possess are identical except color. The thread pitch on both ends of the L7, L6 are the same with the tail end of the M3 and M3-C. These match the thread pitch of the extensions. The thread pitch on the head end of the M3 and M3-C are not compatible with the extensions.
From your post, I would deduct that the head (female) threads on the M3 are trapezoidal so they don’t accept the square (male) threads of the extender. Pennzy made a detailed observation of the M3-C to be square which I now understand as the tail end, not the head end.
Then it’s not as much as thread pitch but form. A female square thread will accept a male trapezoidal thread. So the tail ends of these lights could be square and would accept the extenders.
In essence, they (all colours) fit the tail ends. The head thread form on the M3-C isn’t compatible with all (or any) extenders?
So strange that Simon doesn’t state so on his site nor did he in messaging, and the discrepancy in the product page/picture.
