Many climbers rig a chest harness from webbing, but these are difficult to adjust as layers change and the carabiner is likely to smack them in the face during a fall. The Figure 8 chest harness is superior to any rigged chest harness. The buckles are located under the arms where they are out of the way of pack shoulder straps. Use a locking carabiner to clip the chest harness to the rope that is tied into the sit harness.