Wurkkos HD20 - Brand: Wurkkos - Model: HD20 - Included: 2 x 18650 batteries - Max 2000 lumens - Power bank function - Strobe + SOS + Beacon Thank you for viewing. [Good Points] - Headlamp but with strobe + SOS + beacon - Brightness is neither good nor bad - Power bank function [Bad Points] - 21700 is heavy. Therefore, I'm including a bonus: "Liitokala 18650 4000mah 3.7V". The manufacturer is a reliable brand, and the 18650 4000mah is impressive. If you are interested, please search for "Wurkkos HD20" for details and usage instructions (YouTube). [Supplement] I couldn't find Wurkkos 21700 batteries, so please use Sofirn 21700 batteries instead. [Supplement] I initially rated it as "average," but I found a new scratch on the tail cap bottom, so I've changed the rating to "below average." I've also added images.