2003 Chevrolet Corvette Owner's Manual - Page 21

The lap part o the belt should be worn low and snug on f the hips, just touching the thighs. In a crash, this applies force to the strong pelvic bones. And you'd be less likely to slide under the lap belt. If you slid under it, the belt would apply force at your abdomen.This could cause serious or even fatal injuries. The shoulder belt should go over the shoulder and across the chest. These parts of the body are best able to take belt restraining forces. The safety belt locks if there's a sudden stop or crash, or if you pull the belt very quickly out of the retractor. Lap Belt Cinch Feature If you do not want the lap belt to move freely, pull the lap belt out all the way to set the lock. To permit the lap belt to move freely again, unbuckle the belt, let it retract all the way, and buckle up again. 1-14