Hedwig is a 145mm true X 3" frame with a 2.5mm bottom plate and a 1.6mm top plate. The front and rear are 3d printed TPU, with 15mm of stack height. Hedwig is made specifically for the Furious Pico BLX FC, and will not fit a standard 36x36 fc. AUW with battery is easily under 250 g.
Read more about it here.