I have the A2 bought in early 2018 and just received the current A3 Gen 4 aluminum body version. Very similar but the A3 has grown a bit in size and the battery capacity has almost tripled from 130 mAh to 350 mAh. Maximum output has increased to 650 Lumens claimed. Still a very compact key chain light and I definitely like the current USB C charging compared to USB Micro.