Ultralight First Aid Kit: Which Size for Your Trip
How we did this: we read Adventure Medical Kits’ own pages for its Ultralight/Watertight range, checked on 29 Sep 2026, including the group size and trip length AMK rates each kit for. This is not medical advice; take a first aid course.
An ultralight first aid kit should match your group and trip length, not the biggest kit on the shelf. Adventure Medical Kits rates its Ultralight/Watertight range that way: the .5 (3.6 oz, $31.99) for two people on 1 to 2 days, the .7 (5.8 oz, $44.99) for one or two people on up to 4 days, and the .9 for up to four.
Ultralight first aid kit sizes
| Kit | Weight | People | Trip length | Price |
|---|---|---|---|---|
| Ultralight/Watertight .3 | Not published | 1 | Day trips | $13.99 |
| Ultralight/Watertight .5 | 3.6 oz | 2 | 1–2 days | $31.99 |
| Ultralight/Watertight .7 | 5.8 oz | 1–2 | 1–4 days | $44.99 |
| Ultralight/Watertight .9 | Not published | 1–4 | 1–4 days | $63.49 |
Source: Adventure Medical Kits product pages, checked 29 Sep 2026. AMK does not list weights for the .3 and .9 on their pages.
Choose by people and days
Multiply people by days. The .5 covers up to four person-days (two people, two days) at 3.6 oz, about 0.9 oz per person-day. The .7 covers up to eight (two people, four days) at 5.8 oz, about 0.7 oz per person-day. A solo hiker on a four-day trip is still in .7 territory by AMK’s ratings; a solo day hike, the .3. For groups beyond two, the .9 is rated for up to four people.
Adventure Medical Kits Ultralight/Watertight .5

AMK describes the .5 as a 100% waterproof kit weighing 3.6 oz:
Check price →“With enough first aid supplies for a pair of adventurers heading out for 1-2 days, this 100% waterproof kit is packed with first aid supplies to clean and bandage wounds, treat muscle aches, dress blisters, and treat other common outdoor injuries.”
Adventure Medical Kits, Ultralight/Watertight .5 page
Ultralight/Watertight .7 and .9

The .7 weighs 5.8 oz and adds capacity for trips of up to four days. The .9, rated for one to four people on one to four days, adds emergency supplies for bleeding, fractures and sprains and, AMK says, two layers of waterproofing.
Check price →What to check before you go
- Your own prescription medications and any allergy treatment you need.
- Enough blister supplies for the length of your trip.
- That you know how to use everything in it. NOLS runs wilderness medicine courses, including Wilderness First Aid.
FAQ
What is the best ultralight first aid kit?
How much does a first aid kit weigh?
Are Adventure Medical Kits waterproof?
What does the .5 kit treat?
Should I take a first aid course?
The bottom line
Match the kit to people times days. Adventure Medical Kits’ Ultralight/Watertight .5 (3.6 oz) covers two people for a weekend; the .7 (5.8 oz) covers up to four days. Add your own medications, and learn to use what you carry.
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