I needed the adafruit nrf52840 board with external antenna but as you may know they only provide a version with a ceramic antenna. So i made couple for myself with couple of modifications and i have 2 extra for sale.

Features:

ARM Cortex M4F (with HW floating point acceleration) running at 64MHz 1MB flash and 256KB SRAM Native Open Source USB stack - pre-programmed with UF2 bootloader Bluetooth Low Energy compatible 2.4GHz radio (Details available in the nRF52840 product specification) FCC / IC / TELEC certified module Up to +8dBm output power 1.7v to 3.3v operation with internal linear and DC/DC voltage regulators 21 GPIO, 6 x 12-bit ADC pins, up to 12 PWM outputs (3 PWM modules with 4 outputs each) Pin #3 red LED for general purpose blinking Measures 2.0" x 0.9" x 0.28" (51mm x 23mm x 7.2mm) 4 mounting holes Reset button SWD pinout for debugging