Update: Just a heads up to anyone who prefers to put their child in the middle position of the back seat and is looking for a third row X5: After purchasing an X5 with the third row, I can say that I am not able to safely secure a Chicco Keyfit 30 rear facing child seat in the middle seat of the second row. This is due to the plastic trim pieces BMW decided to use on the lower backrest portion of the seat. This design is different when compared to non-third row equipped X5s, which do not have this plastic trim. The hard child seat base butts up against this plastic and does not provide a very secure install regardless of how hard you pull on the seatbelt. The non-third row X5's do not have this plastic, so you can securely put a carseat in the middle position in these vehicles. We have decided to use the outboard seats and the latch system because of this.

EDIT: I just want to be clear that it IS technically possible to install a car seat in the center position. However, the fact that it is plastic on plastic means that the car seat base moves more than the 1 inch maximum suggested by my seat manufacturer. The install in the outboard seats is much more secure and the base doesn't move more than 1 inch. I wouldn't personally feel comfortable putting my child in the middle with how much the seat moved around.

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Profeshenal spellar