How does the LATCH system work for securing a child restraint?

The LATCH system uses metal lower anchor bars built into the vehicle and attachments on the child restraint to make installation easier and more secure. To install, attach and tighten the lower attachments to the lower anchors, and if the child restraint manufacturer recommends it, also attach the top tether to the top tether anchor. A child restraint must never be installed using only the top tether — lower anchors or safety belts must also be used. (Page 55)