La Sportiva G-Summit is the new benchmark for high altitude technical mountaineering, developed to satisfy two needs: to be an extremely warm single boot for high altitude mountaineering and be a lightweight and precise double boot for extended expeditions in highly challenging climates. With its unique removable liner and thermal insole, the G-Summit is a customizable product based on the requirements of the user and the terrain/conditions of intended use.

La Sportiva G-Summit Boot Features: 

• Inner shell made with the patented Core-Wrap™ technology maximizes warmth while remaining ultralight.
• The BOA® Fit System makes it quick to adjust the lacing fastener - designed to be opened and closed while wearing gloves in cold conditions.
• Optional liner addition can turn the G-Summit into a double boot for increased warmth.
• Vibram® Dura Step compound offers the best grip for mountaineering excelling in low temps and wet terrain.
• the Ice-Tech™ tread is divided into two sections enhancing performance during ascents and hiking.
• Resoleable, to reduce environmental impacts.

Specs: 

• WEIGHT: 29.2 oz / 830 g 
• LAST: Nepal 
• UPPER: Abrasion Resistant Fabric / TPU Mudguard Shield / Differentiated lacing w/ BOA® M4 Dial System / Weatherproof Zipper / Water Repellent Internal Gusset / Core-Wrap™ Inner Shell / TPU Heel & Toe Caps / PU Techlite Rand (lateral) & Rubber Rand (medial)
• INNER BOOT: 3mm Thermo Reflective PE + EVA Single Density Foam
• INSOLE: 5mm Thermal Insole (Removable) / 5mm Carbon Z-Therm™ (Mounted)
• MIDSOLE: None / TPU Insert For Front & Rear Crampon Attachment
• SOLE: Vibram® Ice-Tech™ w/ Climbing Zone Platform (Toe) / Impact Brake System™ / Vibram® Dura Step Rubber Compound
• FIT: Wide