The Primary Arms The SLx 3x MicroPrism Red Dot Sight does not have a shake awake function. It uses a manual brightness knob to turn on and off the illumination.
It say right in the description that it has an auto live activation feature.
Expert answer is wrong. This does have shake awake
The SLx 3x MicroPrism offers 13 illumination settings with AUTOLIVE MOTION-SENSING ON/OFF TECHNOLOGY and multiple night vision compatibility options.
I have had one for a couple of years and the auto-off/shake-awake works very well. It absolutely DOES have that feature, (and why would you buy one without it?). Conversely, I have a Burris RT-6 LPVO that was purchased many years ago, which does not have auto-off, and I've found it with a dead battery several times- because it wasn't turned off before putting it away. That is incredibly frustrating.