The Streamlight MacroStream 500 Lumen LED Rechargeable EDC Flashlight features 2 light output modes that can be changed by double tapping the switch to change light level. Then by clicking the switch to lock the light on at that level. You can find operating instructions by using the link below:
https://www.streamlight.com/docs/default-source/product-instructions/macrostreamusb_op.pdf
The Streamlight MacroStream 500 Lumen LED Rechargeable EDC Flashlight uses an integrated rechargeable Lithium-Ion battery that charges in 4 hours with the EPU-5200 portable USB Charger (not included). At 500 Lumens, you can expect 2 hours of runtime. At 50 Lumens, you can expect 8 hours of runtime. You can find the portable charger using the following link:
https://www.opticsplanet.com/streamlight-epu-5200-power-pack-w-flashlight.html
Here is the part numbers list for this model: https://www.streamlight.com/docs/default-source/info-sheet-with-part-numbers/macrostreamusb_sup.pdf
It starts on high power. If you push the tail cap button twice without a click it goes to low power. If on the second push you push it to the click it will stay on low power. After you click it off it will start on high power again.