Dildas from different Suppliers - Specs?

I just handed over my Dilda and (3) CR2's to a buddy who runs a machine shop to have him try and make a simple extension tube as has been the subject of many posts - I'm hoping he can come up with something that can sell for under $10, but the question I have is regarding design consistancy from supplier to supplier, I only own the one Dilda (so far) but before I get too crazy into this project does anybody own multiple dildas from different sources that can confirm they are all the same design, size, thread, etc?

Thanks as always in advance!

It's all the same just that o-like is taking the best units while DX sends you anything from 140 to 200mW while o-like will send 180-200mW ones, even 190 if you ask her.

Beware if you plan on selling these tubes though. Manufacturers sometimes change these lasers without mentioning anything is different. Usually its not a major problem, unless they decide to make a change to barrel diameter or the threads in this case.

Ideally, I hope it works out to where he can make these quickly and cheaply (like after work, etc) so I could have him kick out a small batch (maybe 10 units) at a time for me, then I'd be a little more protected from being stuck with a mess of unmarketable extensions!

With 3.6v cr2's available for around $1.75 each shipped here in the US, my goal would be to bundle a package with (3) of the high powered cr2's and the extension, therefore offering an instant 10.8v "hop-up" kit for well under $20 shipped - I think I'll post a "feeler" in the BST forum and see what kind of response I get...

Thanks for the input!

np