SharkRF products were available through local vendors but are now only available direct from the SharkRF website. They support various digital modes and networks as well as having 20mW output compared to most other devices which only have an output of 10mW. Whilst they are good products, they are in a higher price category than other devices.
openSPOT 1 (https://www.sharkrf.com/products/openspot-legacy/)
Their first product (no longer sold) – fairly basic unit, requires a LAN connection and powered via micro USB. No additions such as a micro SD card.
openSPOT 2 (https://www.sharkrf.com/products/openspot2/)
Their second product (no longer sold) – this one has a built in antenna, connects via wi-fi and is powered via USB-C.
openSPOT 3 (https://www.sharkrf.com/products/openspot3/)
This is their latest unit – this one has a built in extended range antenna, connects via wi-fi and has a built in battery. It also has crossmode support as shown here – http://manuals.sharkrf.com/openspot3/en/cross-modes.html#page-top
Below is a comparison chart from SharkRF on their 3 products: