Product Review

Specification:

LED: CREE XP-L V6 LED with a lifespan of 20+ years of run time.
Runs on: Wowtac li-ion 18650 battery (3.7V/3400mAh).
Working voltage: 2.7V-4.2V
Output & Runtime (Tested with Wowtac li-ion 3.6V/3400mAh)

Strobe(1150 lumens / - ), 
Turbo(1150 lumens/ 3 hrs), 
High(460 lumens /5 hrs), 
Medium(140 lumens /18 hrs), 
Low(24 lumens / 6 days).

Peak beam intensity: 19200 cd (max.)
Max beam distance: 277 meters (max.)
Waterproof to IPX-7 Standard (1 meters).
Impact resistant: 1.5 meters.
Dimensions: 140mm*25.4mm
Weight: 89g (excluding battery).
Accessories: Usb Rechargeable Li-ion 18650 battery*1, Cable*1,Spare O-ring*2, Pocket Clip*1, Red Lens Cover*1, Strike Bezel*1

Operation

Turn ON/OFF
Press the tail switch halfway to momentarily activate the light.
Click the tail switch to turn the light on and off.
Change Modes 
When the light is on, one click the side switch within 2 seconds to cycle through low, medium, high, Turbo and SOS.
The mode will be Low if the clicking is over 2 seconds.
When the light is off, quick half-press tail switch twice (without "click" sound) for momentary turbo; half-press twice and click for turbo.
Quick half-press tail switch 3 times (without "click" sound) for momentary strobe; half-press three times and click for strobe.
Memory Function
The light will turn on in the last mode accessed, except SOS and hidden turbo, strobe mode.
Low Voltage Indication
The light will blink twice if the battery is low.

A1S BSS TAC V2 version (black) is Wowtac cooperated with YouTube reviewer BlackScoutSurvival who specialized in outdoor and survival living.