It is the second vehicle based on the Model 3 sedan platform.[5] The Model Y shares an estimated 75% of its parts with the Tesla Model 3,[6] which includes a similar interior design and electric powertrain. Model Y will offer optional third-row seats for a seven-passenger seating capacity,[7][8][9] currently planned for Q4 2020.[10][11] The Model Y fills a smaller and less expensive segment from its bigger sibling, the mid-sized Tesla Model X.[12]