Fiat Abarth 500 2015 Owner's Manual page 36

34 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
Pulling Out The Latch Plate
3. When the seat belt is long enough to fit, insert the latch
plate into the buckle until you hear a "click."
Inserting Latch Plate Into Buckle
4. Position the lap belt so that it is snug and lies low
across your hips, below your abdomen. To remove
slack in the lap belt portion, pull up on the shoulder
belt. To loosen the lap belt if it is too tight, tilt the latch
plate and pull on the lap belt. A snug seat belt reduces
the risk of sliding under the seat belt in a collision.