I went and had my children's car seats inspected by our local injury prevention and highway patrol, to make sure they were correctly installed. i have a forward facing convertible car seat that also has the option for a five point harness which i normally used, because my child was not big enough to use the booster yet. this specific seat, i use the latch system. i learned that for my child's weight, they would no longer be able to use the five point harness and need to use the booster seat function with the rear drivers seat belt. when we went to buckle the belt, we noticed that yes, the lap portion had a locking device so it would not slip, however where the shoulder strap attached and came out of the back panel, did not have the safety stop when tugged on quickly. we tried multiple times to see if it would lock (in the case of a collision). it did not. i then tried the rear passengers side with only the same result. both driver and passenger's in front did work. i did not see any recalls due to this specific concern. *tr