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What Is an Internal Frame Backpack?

I purchased my ultrasonic jewelry cleaner, but before I did so, I did some research. Here is what I found out.

What Is an Internal Frame Backpack?

An internal frame backpack sits directly on the back, and the frame is not exposed. For comparison, an external frame backpack has a frame that holds the pack up and away from the back. Hikers have better balance and stability with internal frame packs, and they can hike through heavy branches easier because the bag does not stick out as far. Internal frames are the packs for rugged and less-traveled trails.

But because these types of backpack hug the body, they can retain heat. To prevent overheating, look for a mesh system sewn in to create a breathable space. Some manufacturers use ventilation chimneys or channels, which are panels worked into the back pad.

The construction of an internal frame backpack begins with the frame. I have only seen these made of aluminum, which is both lightweight and durable. There are a variety of different fabrics used: nylon, polyester, cotton, and canvas. Read the next section on the varying degrees of water resistance each fabric has. Foam is sewn into the shoulder straps, lumbar, and back area to make carrying more comfortable and less grinding. Zippers, plastic clasps, and drawstrings are all standard closures. Some zippers offer more water resistance by having tiny, tightly-fitting teeth.

Views From the Top

Views From the Top

How to Choose the Size

When a new hiker starts looking at packs, they always ask, “What size do I need?” To determine the size, you will need one measurement: the back.

To measure your back length, you will need a cloth measuring tape. Tilt your head forward (don’t hunch over, gently lower your chin to your chest), and feel for the bony protrusion at the bottom of your neck. It should be right about where your neck meets the back. Put your hands on top of the hip bones. The hip bones are the round boney protrusions above the hips and below the waist. Have someone measure down your back the distance between the boney neck protrusion and the hipbones.

Measuring yourself is possible; it’s just not quite as easy. To measure your own back, tie a string or belt around your hipbone area. Follow the instructions above to find your hipbones. Tilt your head forward and feel for the bony protrusion at the base of your neck. Hold the tape measure there and stretch it down your back to the string or belt. Grasp it at the end and read that measurement.

Hiking backpacks come with several ways to adjust them for comfort. Put on the pack and tighten the hip belts. The pads should cover the tops of the boney hipbone protrusions, and the belt itself should clasp around or just below the belly button area.

Next, cinch up the shoulder straps. When you pull in the pack, you should feel the weight shift to the hip pads.

The last step is to clip the chest strap. This strap keeps the shoulder straps from moving around during your hike.

Some packs come with adjustable torso lengths. The lower-neck pad is moved up and down with Velcro fasteners. This neck pad should start at the base of your neck. If the torso and pack measurements are correct, the hip pads should rest on the hipbones. If the neck pad is too high, your shoulders (not your hips) will be carrying the weight of the pack.

Issues For Tall People With Internal Frame Backpacks

Many of the packs today range in torso lengths from 15 to 20 inches, which may not be long enough for very tall people, or even shorter people with long torsos. Remember, it’s the length of the back that matters, not the person's height. I found a larger internal frame backpack with adjustable and longer torso lengths that had the best fit. The beginning length was 19 inches, but I was able to expand it to 23 inches with the torso adjuster located by the upper shoulders, so it did not interfere with the air cooling channels.

Internal Frame Backpack As Carry On

Internal Frame Backpack As Carry On

What Is the Carry-On Size Limit for Internal Frame Backpacks?

What I discovered is that just because it is a backpack doesn’t mean it can be carried on a plane. A carry-on bag can only be 9 inches by 14 inches by 22 inches (22 cm by 35 cm by 56 cm), straps and everything. The packs I found that could hold several days of supplies were too large to be stowed in the overhead compartments. I had to make a choice when traveling by plane to my hiking destinations. Either bring a smaller pack and pack less stuff, or check a larger backpack. I look at it this way: this bag serves as luggage and hiking gear.

My go-to carry-on internal frame backpack has pockets where you can quickly get at headphones and devices without having to rummage through the entire sack. Plus when traveling by plane, you need a place where you can put your liquids so that you can take them in and out for TSA, and this one has a front pouch.

Another option when looking for a carry-on size pack, is to find one with a removable waist belt. The belt can be detached and stored in the pack; just make sure you leave room for it when packing.

Most airline rules agree that if your backpack meets the size requirements, it can be your larger carry-on piece. If your pack is full to the brim, take a smaller bag or purse as your personal item. Store the backpack in the overhead compartment, or in the extra baggage space some airplanes have upfront. Use the smaller bag to keep headphones, tablets, and other things you will be using during the flight.

Men's Vs. Women's Backpacks

Men's Vs. Women's Backpacks

Difference Between Backpacks for Men and Women

Some companies market backpacks to genders. The claim is the women's are narrower at the top around the shoulder area because most women are smaller than men at the shoulders.

Adjustable backpacks made for people in general can fit smaller frames and can be fitted to women. If you are a tall women, see the section on fitting issues for tall people.

Some of the women-specific backpacks have brighter colors like teal and lavender, and they may be made smaller for lighter loads. The best advise is to look at all packs first. Sometimes it is just a marketing plan when they create gender-specific items.

For example, one company makes a women's style, which weighs 3 pounds 2.1 ounces. The men's version is 3 pounds 2.8 ounces. They both are exactly the same size and carry the exact same capacity. If it is marketed as a women's version. You should take a look a the men's version to see if there really is any difference.

Backpacking Through The Mist

Backpacking Through The Mist

Internal Frame vs. No Frame

A pack with no frame is basically a bag with shoulder straps. Packs like this are very light and inexpensive, and perfect for a few hours or a day trip, but they are not meant for long hikes. Bulky items do not sit well in a no-frame pack, and there is no support or foam.

Beach Backpacking

Beach Backpacking

Waterproof Packs

When you are heading out to a rainy climate, keeping things dry will be important. There are varying degrees of water-resistant packs. Water-resistant fabrics are nylon or polyester treated with a protective coating. The coating is polyurethane. There are some other products used also. These ingredients force the water to bead up and slip off. It is not waterproof. Eventually, the inside will get wet. Water-resistant and water-repellent labels are used interchangeably. Rain and water can seep in through the zippers.

Waterproof offers a higher level of dryness than either water-resistant or water-repellent. To keep a pack dry the best option is to cover it with a dry sack or cover. These bags and covers are made of plastic or polyurethane. The fabric is extremely lightweight. Many packs come with dry covers sewn into them, so during a downpour, all you have to do is unfold the sack and cover the pack. It’s very convenient.

DIY Waterproof Your Backpack

Detachable Daypacks And Other Useful Things

When I first started hiking and backpacking, I just used a very basic bag. When I got more experience under my belt and talked to more hikers, I was able to look for features that could help me. Each person has different needs to fit their comfort level and hiking areas. Here are some things I have learned about along the way.

If you are traveling with a larger pack, one handy addition is a removable daypack. There have been countless times where I have dropped the big pack off, unhooked the daypack, and off I went. It’s like having a purse or fanny pack, but you don’t have to lug it around all the time.

Hydration packs are water reservoirs or bladders that store clean drinking water. There is a drinking straw or tube for easy access. When hiking in the summer, these are a must. The packs hold anywhere from one to three liters of water. You usually have to buy the hydration pack separately, but the backpack should have a spot made specifically to carry hydrations packs.

Backpack With Detachable Daypack

Internal Frame Advantages And Disadvantages

There are many pros and a few slightly negative issues when it comes to hiking with internal frame backpacks. One of the best advantages is the pack helps you keep your balance when traversing rough territory because it sits closer to your body. It does not sit above you like the external frame packs.

They come in plenty of sizes from the smaller carry-on pack to the styles roomy enough for long outback trips. They also fit short and taller people, and both men and women can wear them comfortably. Because there is no exterior frame, they also are easier to store, check on airplanes, and fit into vehicles.

Some of the qualities that make it user-friendly are also its disadvantages in some ways. Because the pack sits closer to the body, it does cause more warmth, which can be an issue in the summer months. The air channels and cooling chimney help dissipate the heat.

Mountain Backpacking

Mountain Backpacking

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.