I didn’t bring a sleeping bad with me on 100 Nights of Summer. They tend to be bulky, take up much needed space in the pack, and I end up passed out on top of it rather than inside it. In the name of experimentation, this summer I opted for the humble sleeping bag liner.

This is the Adaptor Coolmax Liner from Sea to Summit that I used. I heartily recommend picking up this piece of gear for your festival and all around travel life (see #3 below).

Sea to Summit Coolmax Liner

Photo Credit: Sea to Summit

Here’s what I learned:

Yeah, I probably should have brought a sleeping bag: Six days over two festivals made me reconsider my decision. The aptly named Hurricane Festival found me bundled into all my clothes during the first night of chilling rain. And of course, Ireland isn’t known for their warm weather nights.

But I learned a thing or two about cool weather camping: (1) Bring a knit cap. (2) Stuff your unworn clothes into the liner for added insulation. (3) Find a tent mate. (4) The local liquor helps with sleeping. (5) Forget sleep — stay up all night.

The liner is perfect for backpacking: I traveled hard during 100NOS and during those hauls I spent the night in odd places. For sleeping at the airport, on the train, the deck of a ship in the Adriatic sea, the floor of a ferry, or even on a slightly cool night with the tent door open, this sleeping bag liner was perfect.

More experimentation is needed: There’s a hybrid bag out there with my name on it and I aim to track it down. It needs to be as small and as lightweight as the sleeping bag liner, but with just enough warmth to keep the edge off a chilly, rainy night.

The Review: 4.5 out of 5. The size and weight of the Sea to Summit makes it an ideal addition to your backpacking arsenal. I used this piece of gear way more than I anticipated. I only wish it was slightly warmer.