Lexus RX300 2001 Owner's Manual page 152

If your child restraint system has a top strap, it should be
anchored. (For the installation of the top strap, see "Using a top
strap" on page 129.)
For the installation details, refer to the instruction manual
equipped with each product.
" Type B
1. Widen the clearance between the seat cushion and
seatback a little and confirm the position of the lower
anchorages below the tag in the seatback.
2. Latch the buckles onto the anchorages.
2001 MY RX300_U (OM48431U)
COMFORT ADJUSTMENT
16R318
133