It wasn't expensive but it still isn't worth it
I ordered a Wurkkos HD01Pro and was extremely excited. A friend had one and I was impressed, couldn't wait to share with all of my coworkers at an aircraft performance center. Received the flashlight, charged it until it showed green, went to turn it on and the light flashed once. It doesn't matter which of the two power buttons I press it is the same result: flash once. I tried locking/unlocking and every other sequence listed in the manual still just one flash per button press. I emailed the company and have not received any communication from Wurkkos. As I said, I was excited to show all the other mechanics and avionics personnel on the floor, but I didn't realize I was going to be showing them a product they should avoid.