The Forty Below® Purple Haze overboot


Available in stock

Quick Overview

The Forty Below Purple Haze overboot is a favorite insulated boot cover choice for use on Denali, Himalayas, and Polar expeditions.  It fits Double shelled mountaineering boots, and single mountaineering boots. 

Please see below for more details.

To Order: Please provide details about your boots and crampons in the boxes below. We will select the proper size for you based on your boot information. The crampon information is to be able to pass on any special fitting notes if needed.

1st Color Choice *

2nd Color Choice *

Your Boot Details

Crampon Binding Style


The Forty Below® Purple Haze™ overboot has been a favorite insulated boot cover for decades by climbers worldwide, becoming a top choice for use on Denali, Himalayas, and cold weather expeditions. 

It is a knee height and full length insulated overboot for mountaineering, and is patterned to fit over double shelled and single mountaineering boots.  It is a very unique overboot in that it can stretch to fit easily over a wide range of double shelled mountain boot models, and also the large volume “combi-boots” such as those from Millet, La Sportiva, etc. They also fit nicely over large volume single mountaineering boots such as the La Sportiva Nepal for example.  It is important to point out that they no longer will fit over any type of AT ski boots or snowboard boots anymore, as those types of boots have changed in their shape, so we now make the Forty Below® Fresh Tracks™ model for those boots.

The Forty Below® Purple Haze™ is easy to put on in the cold, and fits trim to the boots and leg area.

Key Features:
Full length insulated boot cover.
Easy and fast to put on in the cold and at high altitude.
Fits over double shelled mountaineering boots, and large volume single mountaineering boots.
Completely stretchy to fit a wide range of boot models.
Fit with a wide range of crampons styles.
Easy to repair.

Crampon Compatibility:  Forty Below® overboots fit with a very wide range of crampon and boot combinations.  Below is a chart to show possible combinations:

Double Shelled Boots:
The Purple Haze can fit with Double Boots with these types of crampon bindings:

Purple Haze With Strap On Binding
Strap on binding.

Purple Haze With Strap Toe Flip Lever Heel Binding
Strap toe/Flip lever heel binding.

Purple Haze with wire toe bail binding
Wire toe bail binding.

The Purple Haze can fit with Single Boots with these types of crampon bindings:

Purple Haze With Strap On Binding
Strap on binding.

Purple Haze With Strap Toe Flip Lever Heel Binding
Strap toe/Flip lever heel binding.

Please Note: Single boots will usually not fit with overboots and wire toe bail crampon bindings because of the lack of space on the toe for the bail to properly fit, which is why they are not pictured above.
WARNING: The user must try on the crampons to each boot and overboot combination to confirm a proper fit!  Some crampons will not fit certain combinations due to the condition of the boot, crampon, or shape and size relative to the shape and size capabilities of the crampon.  The user must confirm proper fit prior to using. Please contact if you have any questions or need assistance.

Please click here to read the PDF document comparing the Forty Below® Purple Haze™ and Forty Below® K2 Superlight™ overboots: Compare PH and K2 2014

Check out this video of Ed Viesturs about the Purple Haze:

Special thanks to Ed Viesturs and Whittaker Mountaineering/RMI for using our gear, producing this video, and letting us share it with you!

For more information about all of our different models of overboots, please go to the All About Overboots Section,  which is located on our home page.  There is an overview of the different models and the boots they go over, and additional information about overboots and insulated boot covers.


Copyright ©2019 Forty Below, Ltd

Product Photo Gallery:
Put the cursor over the picture to see the heading. Click on the picture to enlarge it and to view the full description. An arrow on the edge of the picture will enable forward and back movement through the set of pictures.

The Forty Below® Purple Haze™ model overboot is a completely insulated overboot for mountaineering boots, primarily double-shelled plastic boot styles.

It is knee height, and completely insulated using a special nylon covered, 4.7 mm stretchy neoprene closed cell foam insulation, with 2 layers of heat reflecting Titanium between the foam and the nylon.  The insulation goes completely around and under the boot, with no gaps in the insulation.  The insulation panels are glued together, and also stitched on the inside and outside surface, with no sewn through seams.  They fit trim to the boot, and are not bulky.

They fit with a wide range of crampon binding styles such as “step-in”, “new-matic/hybrid”, and  “strap-on” crampon bindings.  The toe and heel area have small triangular shape panels made of a slightly thinner neoprene insulation that allows for many wire toe bails and flip lever heels to simply compress the insulation and rest on the toe and heel groove of the boot.  The toe, heel, and lower side area of the overboots have a thin rubber paint applied to add abrasion resistance and help protect the stitching.

The closure is in the front using a large size YKK® HEAVY DUTY zipper, with a flap underneath to help keep snow out.

Forty Below® overboots are very easy to repair and maintain.  The common crampon poke holes are easily glued back together.  Please see the info sheet provided with the overboots, and also the Repair Section of this website for more details.   

ORDERING: Please use the fill-in boxes above to provide information about your boot and we will select the proper size overboots for your boots.   We need your boot Brand, Model, Size, and a measurement of the bottom of the sole from the heel to the toe.  Measure using either inches or cm.

Built in the USA!  Handcrafted in the USA. We use materials from the USA and our friends from other Countries around the world.

OVERBOOT SIZING: Forty Below® Overboots are made with stretchy insulation materials, and have a wide range of different sizes and shapes of boots that a particular overboot model/size can fit.  Because of this wide range, we ask that you provide some basic information about your boot and crampon, and then we will select the proper size with that information for you.  Please use the fill-in boxes above for ordering.

SIZING: XS-XL To fit from ladies 4 to mens 16 double shelled mountaineering boots.

COLORS: Black, Navy, Purple.  (Red not available at this time)

WEIGHT:  1lb 8 oz. (672g) per pair size Medium.


Additional information

Weight 1.25 lbs