Sleep sacks

[dannyvp]

Has anyone made a coolmax or thermo heat sack.
I'm thinking about a sack I can put under my quilt like a sleeping bag sack.

[SnrMoment]

Define "sleeping bag sack." Stuff sack, sock? other?
Under your quilt? Underquilt, top quilt?

[dangerous]

I have taken an off the shelf sleeping bag liner and opened it up to function like a top quilt. I use it in the heat of summer, then use it inside my TQ when it's really cold outside.

[dannyvp]

I was thinking of a sleep sack idea, maybe to be just a thin, really thin top quilt.
There are several sleeping bag sacks out there but they are around $50 and I don't know anyone with one.