Different Kinds of Backpacks
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Backpacks are widely used today not just for outdoor activities but also for special purposes such as carrying laptops, cameras and the like. The types of backpacks are manifold and it’s quite impossible to practically list all the types of backpacks. However, if we generally classify the types of backpacks found today, we can easily make 4 categories; external frame packs, internal frame packs, bodypacks and frameless packs.
The design that supports the pack and at the same time distributes weight across the body in such a way that most weight is put on the legs and hips is known as a pack frame. Unlike other designs, with this one, the weight is not directly put on the shoulders through straps. This way, the chances of shoulder injuries are reduced. Remember, backpacks that only come with shoulder straps can affect the posture of a person if more than 14 kg weight is carried on it. This is the reason why most backpacks today come with a zipper, buckle mechanism or a dry-bag type closing. Some models also do come with a drawstring fixed with a cord lock for the main compartment.
Internal Frame Backpacks:
Internal frame backpacks were first introduced in 1967 by Greg Lowe. He was the founder of the companies Lowe Alpine and Lowepro. Both of these companies specialize in making carrying bags and backpacks. An internal frame backpack has an inner frame that is covered by a large section of fabric. The inner frame is made of strips of aluminum, plastic or titanium. In other words, the inner frame is quite lightweight. The best part of such a pack is the way the straps are placed. They are attached in such a manner with the inner frame that they distribute the load appropriately and doesn’t let it shift. In addition, such packs fit closely to the wearer’s back in such a way that it minimizes movement and shifting of load. Such backpacks are ideal for activities where a lot of upper body movement is required such as rock climbing, skiing and the like. Moreover, since the inner frame allows more fabric it also allows more space for compartments. Some inner frame packs also come with lash points, webbing loops and straps to hold sleeping bags. The downside of these packs is that since they fit closely, there is less space for ventilation and sweating becomes a problem. Also, since the frame is inside and is lightweight, it is nearly impossible to attach heavy equipment externally with such packs. Initially when they were introduced, these bags were uncomfortable to wear and didn’t allow much space for items. However, with time, these issues were addressed and today are being widely used for various outdoor activities.
External Frame Backpacks:
External frame backpacks were actually designed to carry heavy weight such as weight from 20 kg and above. It gives the wearer more protection and support. Also, an external frame backpack distributes weight across the body points better than the other types. External frame packs have been in use for centuries. Wooden pack frames were the first external backpacks mankind invented. External frame backpacks are usually used in military and mountaineering applications. Metallic external frame packs were introduced in the mid 20th century.
Today, most external frame packs are made from aluminum or other lightweight metal alloy. Today, even plastic and reinforced synthetic polymers are being used for such packs. These packs have a system of straps and tight netting to avoid the metal frame from hitting the wearer’s back. Not only is this meant for comfort, it also serves the purpose of providing enough ventilation to the user’s back. This is why external backpacks are considered much cooler than their other counterparts.
Another major difference between external frame packs and internal frame packs is that of the fabric portion. External frame packs come with a fabric sack like portion. The frame is exposed from the top and the bottom of the sack so that other items can be attached to the pack externally. Moreover, this sack can completely be removed if there is the need. This way, the user can easily customize his load by carrying his items the way he wants to instead of just putting it in the sack. Do you know most backpacks used by the marines are usually external framed ones because such bags can carry items of various shapes and sizes?
Frameless backpacks are probably the most commonly used form of backpacks. These backpacks come in various shapes and sizes and can be used for a number of purposes. These are simply bags with two shoulder straps to carry load. The simplest form of such bags consist of just one pocket while other more complex designs can consist of various compartments for various items. Some elite designs also come with waist straps, additional pockets, padded shoulder straps and padded lower back area. Some models also come with reflective materials on the pack for nighttime safety. These bags have become so common today that they can be easily purchased at cheaper prices. Moreover, at times hikers and other activists and athletes prefer using frameless backpacks rather than the framed ones because of their being lightweight quality.
Packs for Special Purposes:
Apart from the above given categories, there are other types of backpacks as well that we see and use in our daily lives. One common example of such a backpack is the school bag used by kids. It definitely is a mini backpack with simple straps and no frames. On the other hand, we have backpacks like the ones used for laptops and cameras. These are special purpose backpacks with no particular frames or straps. Everything about such bags can be adjusted as per the need.