The IA3K is a great addition to the most versatile hunting pack system on the market. It’s the perfect “Run-n-Gun” pack system!
At 3,475 cubic inches with the lid (2,950 without), the IA3K is perfectly sized for everything from day hunts to 3–4 day backcountry hunts.
When the hunt is successful, the IA3K is built for the haul. Meat can be securely carried between the Integrous Frame and the bag, allowing you to haul your harvest without sacrificing valuable space inside the bag.
For even greater load-hauling versatility, add the Pannier Load Carrier. The Pannier keeps heavy loads high and secure to the frame for better balance, stability, and comfort.
2950 cubic inches without lid (3475 ci with lid)
5 lb 6 oz
Fits the existing Frame and Suspension
Seamless transition from 5k or 8k bags to 3k in a matter of seconds.
YKK zippers
Main compartment has Horseshoe-style zipper.
Large 300 ci expandable pocket on outside front panel allow quick access to gear used most often such as insulation layers and/or raingear.
1 nylon pocket on inside of the main compartment keep smaller items handy.
One side expandable mesh pocket to provide quick access to items such as your beanie, gloves, or even your bathroom kit.
One 19” side pocket is ideal for even the largest spotting scope.
One 7” side pocket designed to handle tripod needs or will hold a rifle stock for side carry.
If you go through the steps below and are still uncertain of your size or if you just need additional help, please contact us and we'd be glad to help!
How To Measure Your Torso for Frame Size:
You'll need someone's help, so grab a friend!
Bend your head down and find your C7 vertebrae - it is the one that protrudes out. That will be your starting measurement point.
Find the top of your hip bones and form a straight line across your back. That is your ending measurement point.
For a visual of this process, check out our video below:
How To Measure Your Hip Belt Size:
Our hip belt sizing is based off of your pant size. So whatever your pant size is in inches, would be what you use for your Hip Belt Size.
The triaxial carbon fiber structure combined with additional strategically placed composite materials provides the greatest strength to weight ratio on the market. We are confident in delivering a frame that is not only comfortable, but provides the ability to haul extremely heavy loads.
The key to the frame’s design is its shape. This allows the heaviest load to be positioned in the center of your back by spreading the weight over your hips, minimizing muscle fatigue and shoulder strain. To stay cooler in hot conditions, the shape maintains air flow around your back. The frame also follows the natural curvature of your spine, providing extreme comfort in all conditions.
We offer a 1-year warranty for any material defects and workmanship to the original purchaser.
The Integrous and Invictus Frames have a LIFETIME GUARANTEE.
Yes. All IA packs work off of a single frame and suspension system. You can interchange the bags and Pannier Load Carrier at will. No need to buy a separate suspension system.
The material we use is a 500D Cordura which is very water resistant but not waterproof. If your hunting in wet environment, we recommend out IA Rain Cover.
Yes. We have the Integrous Frame for torso lengths from 18-22".
And our Invictus Female Frame for torso lengths 13-17". This frame will also work for kids who fall into that torso length range.
We have a pro program that includes our Military and First Responder Program, Guide and Outfitter Program, Industry Program. Apply Here: Pro Program
I bought this pack for my son for a Christmas gift. He was so excited to use it last weekend to pack out a mountain lion that weighed over 250lbs. He’s also a EMT so he had all his medical supplies, hunting supplies and was able to easily pack everything out comfortably.
Great pack system! IA3K with the pannier. Team was excellent in helping ensure I had a proper fit and took time to videochat to ensure everything was correct.
Amazing pack! When i ordered it I wasn’t sure if it would show up in time for my elk hunt but it did. It was super simple and easy to use even with a few minutes to get it all set up. I was able to pack over 100lbs of meat out with it, no problems. Best pack I have ever used.
I try a lot of different bags at my outfitting company. Initial Ascent has been on my radar for a long time. I finally pulled the trigger and got one for a 6 day back country hunt in Spain. The bag a frame system were solid, probably better than I expected. I recommend.
Best. Pack. Ever.
I used to use mystery ranch packs, but it struggled with half of an elk last year, and it was just an uncomfortable pack out. I am recovering from multiple hip surgeries that ended up with my getting a total hip replacement. So I wanted to upgrade to something that is made to carry meat without a problem, and will fit me well
Wearing this pack without meat on it. I almost forget it’s there. Even with the stiffer frame. It is comfortable and just fits me perfectly. I got the pack two weeks ago, and decided to take it up on a fall bear hunt where I shot my largest bear yet in a very steep and thick canyon. I took 4 trips, with anywhere from about 70-100 lbs each trip and it was easy as can be. I’d recommend this pack to anybody who is going to be packing out meat. You can feel the weight in your legs. But it all rides so well, it is a very easy pack out.
Their pannier system. Love it. Nothing will slide or shift on you. And it rides right where you want it. I love that it came installed on my pack so I didn’t have to do it myself.
The Great - soo much more comfortable than my previous pack, and it was so much easier to adjust after watching the companies videos on how to set it up. Putting it on has been super easy even with my bino harness on, no snagging harness or difficulty getting the second strap to cooperate with my arm.
The good - the pockets are spacious and easy to get in and out of. Fairly easy to set up the bag with the Pannier load carrier.
and if I had a negative - tri glides on the pannier load carrier and the load lifters are a little difficult to push through or remove the first time through the carbon frame but after you do it once they become much easier. I found pulling the strap tight on the tri glide as pushed it through helped prevent it from bunching up and binding the tri glide.
Other tips/suggestions - grab a couple of smaller bags to sort your stuff you throw into the lid to help with organization....and a small bag on the hip belt has been nice for quick snack and a couple key pieces (call, smoke bottle, etc)
I love this pack. It’s comfortable to wear, easily adjustable, fits me perfectly and I’m already preparing for the Hunt by putting weights in it. It’s very comfortable.
The IA3K Pack System is exceptionally well thought out and built for real-world use. Fit and weight distribution are excellent, even when fully loaded, and the suspension system remains comfortable during long days in rugged terrain. Stitching, materials, and hardware all feel durable and purpose-built rather than overengineered.
The modular layout makes organization intuitive and efficient, allowing quick access to critical gear without unnecessary movement or noise. Adjustability is a standout feature—this pack can be dialed in precisely for different body types and mission requirements.
Overall, the IA3K Pack System performs exactly as expected from a professional-grade load carriage system. It’s reliable, comfortable, and clearly designed by people who understand field demands. I would confidently recommend it to anyone needing a dependable pack for extended operations or demanding conditions.
Love the pack. Fits great. Feels even better. I’ve always rocked mystery ranch. But after my last pack out I knew I needed a change for something better. This pack is sturdy and I love the way it is configured. Can’t wait for a more comfortable pack out this year with this new pack.
This is the most comfortable pack I've ever owned. Added 60lbs to the pack and walked around for a while and didn't even notice. The way they weight is distributed is literal perfection. I can't wait to use it this Hunting season and have been recommending this pack to everyone. Excellent job Initial Ascent! I'm a lifetime customer.
We will see what it can do spring bear starts in 2 days I bought because of Brian Call and Ryan Lampers the most savage hunters out there I trust there opinion !!
Great fitting comfortable pack. Frame and pack far exceed my Kuiu. The only thing I would like is an option to mount a lower small pack or detachable fanny pack on the pack frame for short hunts.
I recently purchased this pack, without further ado……. The frame is the best I’ve ever used! The pack is easily accessible and built with quality materials. With the accessories I purchased I feel it will make my packing a better experience. The competition has a lot to catch up on after seeing this well engineered pack. Thanks for making a great product.