Here is a compact 4K Windows 10 PC that can fit in the palm of your hand. The CHUWI LarkBox Pro measures 61 x 61 x 43mm, weighing only 127 grams. It has a J4125 processor with quad cores, Intel UHD Graphics 600, 6GB RAM, and 128 eMMC. It has a Micro SD reader that can handle up to 128GB cards. You can also upgrade its storage to 1TB with a M.2 drive.
This mini PC comes with dual-band WiFi. It also has Bluetooth 5.1 connectivity. It supports VESA mounts. While the LarkBox Pro runs Windows, you can also use Linux on it.