In order to turn the stroller into a double, a sold separately double conversion kit is required. There are 16 unique seating combinations from double tiered car seats to a bassinet and a single seat. The only seating combo it doesnâ??t do is a double bassinet option. The City Select features Baby Joggerâ??s famous Quick-Fold Technology making it the only in-line stroller to fold flat in one simple step. With a 45 lb per seat weight capacity, the City Select will last you through your stroller years.