Litter bridles for use in challenging environments are my most specialized projects. Most of the bridles pictured weigh around 230gm/8oz (without carabiners), which is a small fraction of the weight of any other bridles that I know of. You can literally carry these in a coat pocket. 
 
They are made from polyester rope, which is easy to get a grip on when moving around the litter suspended. Each v-bracket, the front and the rear, will hold over 17kn. This is stronger than the vertical rating on any litter I am aware of. In the horizontal configuration, the strength may potentially vary depending on the angles, but it would take very extreme angles to reduce it to less than 20kn.
 
There are endless possibilities with litter bridles. This product page is really here to get your attention, I highly reccomend that you fill out the form at the end to enquire about a bridle to meet your needs. Some of the options can be:
-Adjustable bridle legs
-Different top closures involving steel or aluminum rings, rigging plates, etc.
-Integrated set-of-fours, or designed to have one easily swapped in.
-Other designs to convert from horizontal to vertical
-Different materials
Fill out the form here:  https://docs.google.com/forms/d/e/1FAIpQLScMoMubFNxAYHptr_GfgFuh8Jb_r72uDRwJBtIDTDq021FyLw/viewform?usp=sf_link