Hello survivalists of reddit.

I am preparing for the High Lonesome 100, a big mountain ultra trail race in late July here in the Sawatch Range of Colorado. Part of the required kit is an emergency bivvy.

I have to carry this during the crux of the race: Climbing Mt Shavano (14,231 ft) in the middle of the night, after having already run 60 miles, so weight is a huge consideration.

The race director has recommended the SOL Emergency Bivvy which comes in at 3.8 oz

I have been looking around for something even a tad bit lighter, even if only getting down to 3.7 or 3.5 oz.

Any recommendations would be greatly appreciated