Need a 500 ma/ 600ma single cell driver

Do you want a light that only runs at 600mA-800mA or a driver?

If so, you are in luck actually.

There is this light which support 21700s with an additional tube:

And you can get this 22mm triple channel driver, only put 1*7135 +1*7135 for maximum regulation, and FET if you really need it.

You can get it built from Lexel: