This flashlight is one of my favourite single aaa flashlights. It uses two step switch, tighten to turn on low, tighten further to go to high mode.
In earlier batches it had SMO, going by serial numbers, so it depends on whether you get the latest. One came from Banggood and the other from Tank007 store.
The last E09 (gray) I bought at FT (March) came with OP.