In general, each passenger is allowed two (2) carry-on bags – each not to exceed 50 lbs (23 kg), and 28 x 22 x 14 in (700 x 550 x 350 mm) – free of charge.
Additionally, each passenger can check up to 4 bags – 2 free of charge and 2 for $20 per bag, each not to exceed 50 lbs (23 kg), 75 linear inches (length + width + height) if the origin and destination stations offer checked baggage service.