Super Light Mummy Style Sleeping Bag

You might be looking for a Wiggy's brand mummy bag.  He uses hydrophobic synthetic insulation and over stuffs so they last forever. Also the big YKK zipper.  It's like a sledgehammer. Heavy dumb and just works.  

Wiggy bags out of grand junction Colorado I slept cold with every fancy ‘outdoor’ brand bag until I was 20. My dad had been using wiggy bags for a decade at that point and I finally switched after having to cut a fishing trip short due to lack of sleep from the cold. Bought a wiggy bag when I got home. Have been sleeping warm for the last 29 years. All of my friends that have made the switch say thank you for the recommendation.

Wiggy sleeping bag. High r value pad like a thick exped. Ignik heated pad cover if you have power. Sleep in clothes so you don’t get cold taking them off then cold again putting them back on in the AM. Get super organized so you’re not wasting time dicking about. Things that you don’t mind doing in summer warmth can get really annoying really quickly in the cold.

Wiggys sleeping bags are amazing, though not the smallest ever.  I would want one in a war zone.

i would look at wiggies over bags, i think that covers 40 degrees. they are a good heavy duty bag, kids are rough. wiggies uses real temp numbers, not just survive the night ratings. if your a larger scout master, they can make you a custom bag 2x wide and 2 x tall. i have ran my 20 degree bag down to about 18 , in a tent . but is way to hot for summmer. but perfect for fall. ive been thinking of ordering a over bag for summer and maybe bring a woobie blanket.

wiggys. they're not light, and they don't pack very small, but if that's not a concern then they're basically the best synth bags you can get.

Wiggys. Super heavy and bulky though. Otherwise you are looking at various 0F and -20F rated bags from Marmot, Sea to Summit etc.

I'm a big fan of Wiggy's sleeping bags with Lamilite(tm) filling. They come in different temperature ratings, and various sizes for tall and wide people.