for shelter in my BOB : a survival blanket(considering getting a different version thats stronger and way better).
also: about 2-3 compact xl trashbags
rain poncho
tube tent-which im considering switching out with a tarp(not a camping tarp) but i would need to stick it into a vacuum sucked air sealed bag(the luggage ones).

my medium kit: a compact orange heavy duty emergency survival blanket it has survival instructions on it ,is very bright and big enough for two people....i forgot the brand..but i think its adven. medical.
rain poncho
xl heavy duty trach bag