Diatone GTB 339 is a 3S 3 inch FPV racer. Included is spare screws, cable ties, replacement battery strap and a buzzer. Built-in is a Runcam Nano 2 camera with a good TBS Nano Pro 32 video transmitter with 25-400mW. Rear is a linear antenna that is well mounted by the TPU camera canopy. At the front I installed the enclosed standoff, so that the camera does not shake while flying. I installed an R-XSR receiver underneath and glued on a silicone pad for the battery. The silicone pad is available in black from URUAV or a little cheaper a transparent pad as I have it that you can use for different use possibilities. The transparent pad is super soft and even washable. The HQ 2 blade propellers are hard and good. The Mamba 1105 motors have 5500KV, which is quite a lot for 3S. The cube weighs 68 grams without a battery and ready to fly with a BetaFPV 3S 300mAh battery 94 grams. Alternatively, there is the GNB battery with 80C which is about 1.5 grams heavier or the lightest GNB 3S battery with 30C, then I’m at 93 grams. The GTB339 is flown with a Taranis X9D transmitter and the HDO FPV goggles. The antennas of the receiver can be brought up nicely through the camera canopy. I additionally protected the antennas with shrink tubing. As you can see, the cube frame is very thin. Especially with the motors there is no protection. Therefore you should fly with it carefully. Finaly, the cube is optimized for speed and light weight, which makes it so special. So the acceleration of such a lightweight is extremely good. And it flies so aggressively fast, so the response and acceleration is so extremely good. that’s just great. I was so excited about the Sailfly-X from my first micro racer, but the 3 inch lightweight is even better for an experienced pilot. I can not get off the throttle. Just perfect. The FPV video is very good thanks to the Runcam Nano 2. I would still take a better camera like the Runcam Racer Nano or Foxeer Predator 4 Nano. The TBS Nano Pro 32 Video transmitter is very good and is soldered on a 16x16mm board. Here I fly with 25mW, but you could up to 400mW turn up the VTX. Yes, and as you can see, the flight behavior of the cube is great. I did not have to set anything under Betaflight. Everything is original settings of Diatone. And the Cube flies great with the 3S 300mAh battery from GNB or BetaFPV. I have also flown the cube with 450mAh 3S Tattu battery. The cube slows down a bit and fills up more like a 5 inch racer. With the 450mAh 3S battery is about 5 minutes flight time with 109 grams of weight. With the 300mAh battery I come to something over 3 minutes flight time. Actually, the 5500KV are too much for the motors. There would be 4500 or 5000KV perfectly enough, but it flies faster. Finally, I flew with a GNB 2S 300mAh battery and that was great too. He also flies fast enough with 2S and with a weight of only 87.5 grams also great fun. So the 5500KV are also ok, because then with 2S well over 4 minutes can be flown. Betaflight 3.5.7 is installed on the F4 FC. If you changed to Betaflight 4, then you could even limit the throttle to 80% and fly longer with 3S battery. Again a good FPV Racer from Diatone.