Like the one in this link ^
I always wondered why these are not offered by convoy.
That was a Convoy flashlight Store flashlight and had the regular trapezoidal S2+ threads.
Simon, the owner of Convoy, has sold several versions of copper S2+s over the years. He currently doesn’t have any for sale, but maybe he will offer them again and I’m sure it would be with the square (or almost square) threads.
Here’s someone that is selling the latest version of the Convoy copper flashlight hosts: Are these copper s2+ (litnit) hosts worth anything?