Toyota RAV4 2018 Manual page 29

Fastening the seat belt (for the rear center seat)
1
Press plate "B" to release. Then
pull the seat belt down toward
the rear seat bottom cushion.
2
Push plate "A" into buckle "A"
until a clicking sound is heard.
3
Push plate "B" into buckle "B"
until a clicking sound is heard.
RAV4_OM_OM0R012U_(U)
1-1. For safe use
Plate "B"
Plate "B"
Buckle "B"
29
1
Plate "A"
Buckle "A"