Wide range VHF and UHF transceiver (144/220/440 Amateur bands included)
SMA antenna connector
Arduino shield compatible with Arduino Uno and Mega
Arduino Library controls frequency, sub audio modes, transmission control, and more. Lots of helper functions to get you started fast.
Cell phone-style TRRS headset jack for analog audio (with optional "cross over" cable for computer interfacing)
ADC audio input (filtered) for digital reception
PWM audio output (filtered) for digital transmission
Plenty of example sketches and library to get you started!