Ah, ok, and thanks for clarifying. The Kioma base is low profile (vertical height), and only 1/2 inch out from the passenger seat upright face (your "fore-aft" distance). It does not extend out past the seating face of the passenger seat, or otherwise hang off the passenger seat. Low and slim generally results in a shorter moment arm from the anchorage point (where the latch/isofix mount points are), so reduces the collision forces for the seat/baby.
The Kioma seat is about a standard length, and the width is narrower than competing seats while fitting the same size baby.
Fun fact: the International Standards Organization (ISO) helpfully defined several envelope sizes (r1, r2, etc) to help with baby car seat standardization, and the EU crash regs (see UN r129) even have a test bar that represents the back of a driver's seat.
The Kioma seat is about a standard length, and the width is narrower than competing seats while fitting the same size baby.
Fun fact: the International Standards Organization (ISO) helpfully defined several envelope sizes (r1, r2, etc) to help with baby car seat standardization, and the EU crash regs (see UN r129) even have a test bar that represents the back of a driver's seat.