@matthewkphx
I would recommend one. ~60,000 Americans bled to death in 2018 and ~2 million worldwide. Most common reason was injury or trauma.
It only takes about five minutes if untreated to “bleed out”, but after the 1st minute of blood loss (20% of volume) you face hemorrhagic shock (you shut off, hopefully your buddy is there to assist you). 2 minutes in 40% loss, fatalities start and it gets worse as the percentage of blood loss increases.
Injuries that can cause you to bleed to death include in order of frequency:
#1 crush injuries from car, bicycle accidents or a heavy object falling (rock, tree limb, falling gear, etc)
#2 gunshot wounds (animation) and blast wounds (shrapnel an exploding propane stove canister, etc)
#3 stab or puncture wounds from a needle or knife or puncture wound from falling into a tree limb, or being punctured by a falling branch, trekking pole or being stampeded or gorded by animals or bite and claw injuries (Mountain lion last month) from bears watch Revenant – it has most of the injuries we are talking about.in one scene
#4 hematoma (a collection of blood, such as a clot, outside of a blood vessel)
#5 cuts or abrasions to internal organs (cracked ribs tearing into organs)
#6 cuts or lacerations to the skin (from walking through a glass door or going through a windshield or an extremity going through the glass (more common).
#7 blunt force trauma from impact with an object (falling from height and impacting the ground). Slipping in a river crossing and current carrying you at speed into rocks (usually head injury, which is a nasty bleeder)
I always carry one, my experience in Afghanistan in 2003 was a life lesson on the value of a good tourniquet and medical kit with everyone trained on how to use it. They only weigh ~3 ounces and you can get a good one for around $20, I like the orange ones which cost little more, but could provide you faster acquisition in an event. Think of a tourniquet as cheap life insurance.
Source: https://www.healthline.com/health/bleeding-to-death