Buick 2006 Rendezvous - Manual (Page 67)

If the vehicle has a third row seat and the seatback
is upright, there is an anchor strap located between
the third row seatback and cushion to anchor the
child restraint for the second row center position
bench seat. If the vehicle has a third row seat and the seatback
is folded down, there is an anchor on the back of
the third row seat for the second row center position
bench seat.
Second Row Center Position Bench Seat with
Third Row Seat
Second Row Center Position Bench Seat with
Third Row Seat Folded Down
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