$500 but there are often small discount offers. Comes with the GPS antenna, but you supply your own VHF antenna. Rather large compared to something like the ACR, and also has a metal case instead of plastic. The class B's are all reputed to use the same motherboard (still) but I haven't checked on that. No complaints at all. Has both an RS232 (9 pin serial) connector fpr laptops and some chartplotters and other instruments and an RS422 (differential) connection for newer chartplotters etc. Upgraded from an SR161 receiver so already had some AIS familiarity, but this was just plug and play. Also has a large button to turn off the transmitter and receive only if desired.