Forty Below® Simple Slipper™ overboots  are an insulation layer that is designed to fit over shoes and boots inside the Forty Below® Light Energy™ overboots.  Please see below for more product details.

To Order: Please provide details about your boot/shoe in the boxes below. We will select the proper size of overboot for you based on your boot information.

Your shoe brand

Your shoe model

Your shoe size

Sole length (measure the bottom of your boot sole from heel to toe in inches or cm)


Forty Below® Simple Slipper™ boot insulation layer

Key Features:
Simple cover to add an insulation layer inside of the Light Energy overboots.
Stretchy closed cell foam insulation.
Reinforced nylon outer fabric.
Heavy duty front access zipper.

The Forty Below® Simple Slipper™ is a stretchy insulated cover to go over lightweight footwear such as trail running shoes and fabric leather hiking boots, to add inside the Forty Below® Light Energy™ Overboot models. 

Very simple to use, just pull on over your shoe and zip it up!  Adds a layer completely around and under your foot.  Designed as an option for use with overboots to help extend the cold temperature range.

Product Photo Gallery:

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Forty Below Simple Slipper in Use:

Forty Below Simple Slippers overboot:

Made of stretchy, strong nylon covered, 3mm thick closed cell neoprene foam insulation.

The panels are all glued together and then surface stitched for added strength.

The large size front zipper offers easy access.

Compact design, so they don’t take up much room in your pack when you are not using them.

Short ankle height


ORDERING: We will select the proper size for your boots from the information you provide us in the ordering fill-in boxes above.

MEASURE YOUR SOLE LENGTH:  To measure your sole length of your shoe, please put a tape measure and follow the curvature of the shoe from the edge of the heel to the end of the toe, following the rubber sole.

SIZING: XS-XXL To fit from ladies 4 to mens 16, plus custom sizes available on request.

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

COLOR:  Black

WEIGHT:  8 oz. (224g) per pair size Large

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