I have been using these Swix Manali insulated shorts for years. The ones I have do have a snap and zipper fly. I cannot tell if the current version has a snap or zipper fly. They do have full side zippers. I wear them over various long underwear and under shell pants or, for colder temps, insulated pants.
Phenix has a version with side zippers , but no front fly as does Elevenate (also no fly, but does have side zippers).
Menali Insulated Shorts 2.0 Ms | Swix
An further developed and customized version of the original insulated shorts
www.swixsport.com
Phenix Adult Training Shorts 2022
Our best selling adult training short! Worn by the Norway Alpine Ski Team, but reproduced for the race community. Four-way stretch and Aerothermo material keeps your thighs warm while you're training and sits tight on the body so not to affect your time. The front facing waterproof zippers make...
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Men's Transition Insulation Shorts
Insulated shorts for lightweight warmth on the mountain. A stretchy and breathable extra layer for ski touring, skiing and all kinds of outings in cold temperatures.
elevenate.com