how do I choose the right first aid kit?

let's assume I want 5 days trek, 3 person kit. The kit must have bandages for large wounds.

The right first aid kit for you depends upon your training and experience. Get training first and you will have the answer to your question. Generally, your first aid kit should contain those things that are hard to improvise (sterile dressings) and will be light on those items that can easily be improvised (splints). Much will depend upon the specifics of your circumstances and the environment.

At a minimum, obtain American Red Cross Advanced First Aid. Even better is W-EMT or similar, but training is the first essential.

I agree with hikermor. Also, your kit will differ based on how far you are from help. A kit for stabilizing serious injuries when you're 15 minutes from help is very different than one where you're 15 days from help.

Agreed. A kit is far secondary to training ( and a refresher course.) And much depends on who goes, when ( season) and terrain.

You could start with on off the shelf kit like AMKs .9 Ultralight and then customize to your needs and to that of your companions. I just posted my own FAK in another thread and my emphasis is on tayloring to suit my needs.

Kits are one thing, training is another. "The more you know, the less you carry." - Mors Kochanski. I have some Wilderness First Responder training but unfortunately I haven't renewed. I will probably just get WFA cert. for my next go around. With training AND experience, you will know what makes the best kit for your own needs and activities. But if you or your companions don't have FA training then a small simple off-the shelf kit is your best bet. Carrying something you don't know how to use is just dead weight.

I already had first aid training.

Some manufacturers organize their kits by the number in a party and the length of the trek. The Weekender is advertised for a group up to six people and trip duration of seven days. This has material for a large wound, like you asked, including material to clean and close it: povidone iodine, 20cc irrigation syringe and wound closure strips.

Some of the features I like about this one is it has 3" x 4" non adherent dressing as apposed to 2" x 3", EMT Shears and 1" tape as 1" tape is easier to work with than ½ tape.

I have no affiliation. I have bought a number of their products over the years.

Jeanette Isabelle

you might look at Chinook Medical (no affiliation)... that's where I got my trauma supplies for my range kit

Most commercial kits are good, but take into consideration your situation, training, location and group size.

...And don't forget to store it in a water-proof way..even a ziplock is good