lap sash seatbelt

noun1

1. •
   (UK, Australia) A type of seatbelt which goes across the pelvis and then up and diagonally across the body; the conventional type found in most cars today.

   • From 4 years to about 11 years, a booster seat, initially with a harness (until about 6 years) and then with an adult lap/sash seatbelt, offers the safest option for car travel. — 1994