How do I pick the right seat depth? What's the difference between the 45cm and 48cm versions? To choose the right seat depth, please follow the measurement method shown in our fit guide video and select the seat depth based on your measurement results. The 45 cm and 48 cm versions differ only in seat depth. The 48 cm version is 3 cm deeper, while all other functions and structural components are the same. Back to FAQs List