The main difference is that the Stomp V2 travel system is sold with an Astral car seat, whereas the Stomp V3 can be sold with our Galaxy and Mercury car seats as part of the travel system.
However both V2 and V3 are compatible with all 3 car seats.
The Stomp range comes with the following items as part of the travel system:
Carry Cot fabric
Seat unit fabric
Carry cot apron
Car seat Hood
Car seat adapters