See History of Kelty Spectra Backpacks for lots of information and pictures about the Kelty spectra packs.

The Kelty spectra packs are likely the most durable packs ever made. All of the stitching is done with Kevlar thread, which is far stronger and abrasion resistant than nylon thread. (On my McHale spectra pack some of the stitching is in spectra, but most is in nylon.) In addition, the shoulder straps and waist strap is made with spectra fabric. Most spectra packs don't have spectra shoulder and waist straps. Most of the things sewn to the pack, such as the daisy chains and mounting points for straps are made of spectra, which I have never seen in any other line of packs. Even the internal frame parts (except the pad) are made of spectra fabric. This pack will survive a tremendous amount of abuse compared to any other pack.

I have three Kelty Cloud 4000 packs. Each of them are slightly different from the others. One has blue and gray trim, the other has all blue trim. This pack is a 4000Reg, and has no side pockets or rear shovel pocket. All of them have a removable, adjustable hip belt. The hip belt is secured to the pack with Velcro and can be moved up or down a total of 2 inches, to allow for different back lengths.

Kelty Spectra Cloud 4000, @2003

Front and Back view

4000g back 4000g front 4000g daisy 4000g bottom

Here are exterior pictures of the pack. The trim is blue and gray for this pack. The third picture shows a close up of the daisy chains that are on the back of the pack. There is a reinforcement layer of spectra under the daisy chain. The daisy chain, like all the daisy chains on the pack are made of spectra fabric, sewn with Kevlar thread. Most packs have daisy chains on the back of the pack, like there. This pack also features a pair of daisy chains on the bottom of the pack, a horizontal pair going around the pack, and a pair on the lid. The fourth picture shows the bottom area of the pack. The two ice axe loops are removable. Also visible are two daisy chains on the bottom of the pack.

4000g strap

This pack has two compression strap which go from one side of the pack to the other side of the pack. These compression straps end in a loop sewn to a red curved piece of aluminum, as can be seen in the picture above. This is how the new 5250 pack works. Also visible are a daisy chain above and below the compression straps. This is for attaching stuff to the outside of the pack.


4000g top top 4000g top bottom 4000g top zipper

The first picture is of the top of the lid. You can see two spectra daisy chains going from side to side. The zipper to access the compartment is at the bottom. The two buckles in the front secure the lid to the main bag. The buckle, loop, and strap with matching buckle attach to the rear of the pack via sewn loops in the gray webbing, and the buckle clips from one side to the other side. All the cloud packs attach the top compartment this way. It is a simple, light, robust mechanism, however there is limited room to adjust the lid upward for large loads. I think there in enough adjustability for the height of the pack extension skirt. (The skirt is made of spectra and is about 6 inches long. The next picture shows the bottom of the lid. The last picture shows the lid zipper. It has urethane coated teeth which makes the zipper more waterproof.

There is a big top section of the pack which has a single compartment, unlike most top sections of packs I am familiar with. I think it would be an improvement if it were divided. It comes off, but doesn't make a hip pack like the current 5250 pack top. There is no internal place for a hydration pack unlike the current 5250 pack.

Shoulder Straps

4000g shoulder

There are two straps that go from the upper pack to the shoulder straps for helping move the top of the pack closer to your body. Their attachment point on the shoulder straps can be adjusted by the slider. There is a sternum strap. The haul loop is made out of spectra fabric.

Waist Belt

4000g belt 1 4000g belt 2

The pack has two small pockets with Velcro inside, on either side near the waist belt. There is also a small pocket with Velcro inside on either side of the waist belt. I am pretty sure this is for the the optional 'levitators', which are carbon fiber springs that attach to each side of the hip belt and are supposed to help with large loads. The carbon fiber springs are enclosed in fabric and there is Velcro to mate with the pack and waist belt Velcro. The upper pocket on the hip belt is for the levitators, and the lower pocket is a gear loop attachment point. Also note the two tension straps on each side of the hip belt. The lower one is found on all large Kelty spectra packs, but the upper one may be to help tension the 'levitators'.

Side View

4000g side

Here is a side view of the pack. Note at the top and bottom of the pack the reinforcement areas where the gear loops can be attached. The mounting points are quite robust. There is nothing in the lid, so it looks a bit odd here.

Gear Loops

4000g loops

You can attach gear loops to a variety of places on the pack as well as the hip belt. This pack has six 'gear loops', which are made out of folded webbing with a clear plastic tube around the webbing. As the plastic ages, it becomes less clear and less flexible. They are often used for holding rock climbing gear, though it seems odd to do technical climbing while wearing the pack. You can clearly see how the plastic has become less clear. I removed all the gear loops, as I don't have any use for them.


4000g lightbeam

The frame is a critical part of the pack. It transfers the weight from the shoulders to the waist area. It is the backbone of the pack. The Kelty frame is made mostly of aluminum. The aluminum isn't flat stock, but rather it is corrugated to be lighter than flat stock of similar outline, and stiffer than flat stock of the same weight. Kelty calls the aluminum LightBeam, which is an appropriate name. The above picture shows both sides of a piece of Kelty LightBeam.

4000g frame_1

The frame consists of two stays of stays of aluminum, and a HDPE plastic sheet which holds them in place. The first picture shows the entire frame. On the left, is the part which mates with a pocket at the inside bottom of the pack, on the other side of the waist belt. The frame rails are partially visible inside the white spectra frame sub-assembly. On the bottom is the HDPE plastic sheet. Also visible is a cross beam of aluminum which can be inserted in the black fabric which is sewn to the HDPE sheet, just to the right of the cross beam. At the far right of the frame is a cross bar which is sewn into the spectra frame sub-assembly. I suspect it is aluminum.

4000g frame_2

This is the other side of the frame. Visible are the HDPE plastic sheets, and where the Velcro is sewn to the HDPE to secure the spectra frame sub-assembly.

4000g frame_3 4000g frame_4

Here is a picture inside the pack, showing the pocket where the end of the frame attaches. The pocket is on the other side of the hip belt. The next picture shows the frame inserted in the pack, and secured with two straps. Visible on the sides, are hydration tube exits to the outside of the pack. This is not present on any of my 6500 packs. I think this is a pretty secure and robust internal frame. It isn't as heavy as the McHale, nor as strong, but I suspect it is strong enough for almost all uses.


4000g repair 1 4000g repair 2

These pictures shows a small rip which has been repaired on the top of the hip belt. It is roughly 3/4 of an inch long on either side of the belt.

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