Both are Garmin kit part numbers for the GTX-335 ADS-B panel mount transponder with internatl WAAS GPS that can be sold over-the-counter without dealer installation.

Both include the transponder w/ WAAS, GA-35 antenna, STC product registration, installation kit, and pilot's guide.

PN K10-00276-04 additionally includes the GAE-12 altitude encoder and high-speed multi-charger.