Graco Contender Slim Instruction Manual page 81

Locking Latchplate and ELR Retractor
A latchplate that holds the lap belt snug after it
has been adjusted; contains a metal bar on the
underside of the hardware that "locks" the belt in
position.
When installing the car seat, route the vehicle seat
belt through the proper belt path and buckle it in.
Then, pull upwards on the shoulder belt so that the
lap belt gets tight around the car seat.
Grab the sides of the seat at the belt path and slide
the seat side-to-side and front-to-back. The seat
should not move more than 1 inch (2.5 cm).
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