Sea to Summit Reactor Sleeping Bag Liner, Standard

2026-03-03T19:00:00

I love this liner, it's so soft.

Sallie S.

Originally posted at

2026-02-21T19:00:00

My son and I both like this sleeping bag liner. He looks like a banana and I look like a spaghetti squash, but despite our size differences, we both fit comfortably in it. It has a gentle warmth when wearing it around camp and the arm free feature is a real winner. It is nice to get in and out of the sleeping bag without having to fuss with the liner getting all messed up - I was always fighting with my other one. I only gave it 4 stars because the hood is a joke. It is so shallow. It does have a draw string, but that doesn't do much except possibly when you are laying down. It would be very cool to have a deeper hood, especially for holding up the back when you are getting into the liner and getting it snapped. The other thing that would be nice is if there was a bit more room when you have your feet out to walk. It makes you take pretty small steps. One other thing I would add would be another snap or two that would hold the length up for when you are walking around camp, as it is, you have to hold it. However, it is still way better than any other liner I have used - the wearing part is genius!

MARYELLEN P.

Originally posted at

2026-02-15T19:00:00

Liner worked very well along with 25 degree quilt to keep me nice and warm during upper 20's temps. I really liked the fact you can "wear" this so you don't get tangled in while rolling over at night.

Peter L.

Originally posted at

2026-02-03T19:00:00

My quilt is only comfortable down to about 40°, but with this I'm good down to freezing. Saved me from having to buy a warmer quilt.

Tammy G.

Originally posted at

2026-01-20T19:00:00

This liner kept me warmer than usual on a 20 degree night out in my 30 degree bag. And my bag was clean after 4 days out. Just had to toss this tiny liner in the wash. Put it in a sink with a dash of liquid soap. Then hang it dry. Very easy.

Jason t.

Originally posted at

2026-01-15T19:00:00

Bought this for my upcoming Kilimanjaro trip. Seems very warm and should pair well with my 15 degree REI sleeping bag

Scottie B.

Originally posted at

2026-01-14T19:00:00

Soft, warm, versatile. . . that's what makes the Reactor so unique. Having the ability to actually wear it around the campsite makes it really versatile. It being super soft makes it comfortable to be in. And finally, it's warm. . . it really works by raising your ability to comfortably handle temperatures around 10 degrees colder than your sleep system is designed to do.

Carmen W.

Originally posted at

2026-01-11T19:00:00

I really like my new liner, highly recommanded

Luc R.

Originally posted at

2025-12-24T19:00:00

Very warm, but quite large when packed.

Masha Z.

Originally posted at

2025-09-25T20:00:00

Fantastic

Terry G.

Originally posted at

2025-09-04T20:00:00

I purchased all three sleeping bag liners for my RV and camp gear setup. We recently camped and forgot to check the weather. It was much cooler than we anticipated and our liners were our go to warming clothes since we had none. I particularly love the toggle for your feet and the snaps to keep it on your upper body and the hood. We use these in our camper, at the camp, and originally purchased for back country camping and its compact nature. Highly recommend all weights. Great product.

Claire B.

Originally posted at

2025-05-09T20:00:00

I bought the reactor sleeping bag liner along with the -9C Spark down sleeping bag. I really like the concept of sleeping systems and want gear that are versatile enough to cover wide range of activities and weather. I used them in Nepal on the Manaslu Trek. I like how the liner allows for walking, usefull at night to get out of the room. If it's warm, I'd sleep in the liner with the sleeping bag opened (like a quilt). If it's cold, you can really feel how the liner adds a few degrees !

Claudia M.

Originally posted at

2024-10-14T20:00:00

I like this one with the hood better than the un-hooded.

George W.

Originally posted at

2024-08-09T20:00:00

Used this liner at 20k and it was that little bit of extra I wanted. Not much extra weight for a lot of extra warmth.

Gwen K.

Originally posted at

2024-05-29T20:00:00

I wanted something I could use during the early camping season in the high country and desert of the Four Corners Region and this works perfectly. I have a double wide 30 degree sleeping bag that I use and in the early spring it still gets cold in the lower mountains. Even in the desert there are cold nights and Im tired of sleeping in my skiing base layers these nights. I've used this liner three times now and love it. The first time was in early April in the desert and it got down to 42 at night. I was very comfortable in the sleeping bag by myself with the liner on. It was a little difficult in the middle of the night when nature called but I managed. The second time I used this was around the end of April and beginning of May at an elevation of 7,000 and lows of high 40's. Once again it worked great and was easier to use in the middle of the night. The key was to fully release the feet cord. The last time I used it was just a week ago in the desert with lows of mid 50's. This time I used my hammock & blankets along with the liner. I was warm and comfortable all night. Overall I love this liner and it meets all my needs for a comfortable nights sleep.

Jason C.

Originally posted at

2024-05-02T20:00:00

I need this liner for my sleeping bag so bad because I'm always cold and when me and my husband camping I always want to me cozy and this liner will help so much! It's great size, amazing material and I love this yellow color!

Anastasiiae

Originally posted at

2024-04-29T20:00:00

This is alright but not something I'd 100% use often. You line your sleeping bag with this liner.. not fully sure how I feel about that. But we shall see..

Brittneyb99

Originally posted at

2024-04-24T20:00:00

This is super lightweight and compact which makes it very travel friendly. The size is pretty great since it opens at both ends and can accommodate many heights. Cozy liner!

Ayeshas36

Originally posted at

2024-04-21T20:00:00

Awesome addition to our camping gear. My son was needing something of this sort since he did not want to give up his other sleeping bag. It is comfortable compact and is just the right amount of insulation.

Digyourdiet

Originally posted at

2024-04-20T20:00:00

Honestly, I had no idea these existed until this campaign. I thought I was selecting an actual sleeping bag! Regardless, my husband loves this product, we went out last weekend and it worked perfectly for him, since he loves to sleep warm. In his words, "This is something I didn't know I needed, but now I can't live without!

Allisonisokay

Originally posted at

2024-04-18T20:00:00

I was very surprised by how much heat this held in from my body heat. It's a very thin material, but it's soft and slightly fuzzy. It was roomy and comfortable. If it was a thicker material, I think I would have felt restricted. It fits in my sleeping bag very easily. I like how you can cinch in the top and bottom to keep the heat from escaping. Even though it's thin, it's pretty durable. It's slightly stretchy, which helps with durability and comfort. It's was very easy to fold and roll back up to fit into its original bag. If you're looking for a little extra warmth added to your sleeping bag, this would be a great liner for you!

Isaiahh12

Originally posted at

2024-04-02T20:00:00

This liner is soft and stretchy, and well sewn. It is thin and good as a liner, but not for adding much warmth. The openings are helpful, but how much weight would a 36-48 inch zipper actually add? It's pretty light, but a liner with a zipper would be better, and ease getting in and out.

Tony

Originally posted at

2024-01-03T19:00:00

Greatly helped us isolate against cold temperatures going down to 24F while tent camping.

Isabelle D.

Originally posted at

2023-12-28T19:00:00

I appreciate the customer service-always delivered promptly and great communication. The product is just what I was looking for-a small light weight sleeping bag liner which keeps my expensive sleeping bag clean and adds a little warmth but doesn't restrict movement.

Charles C.

Originally posted at

2023-12-02T19:00:00

Very comfy.

Ann

Originally posted at

2023-03-08T19:00:00

Comfortable

Amanda

Originally posted at

2022-11-13T19:00:00

It does make a difference, I wish I would have gotten the step above this one. Very light and easy to use, easily fits inside almost anywhere you need to stuff it.

Gary

Originally posted at

2022-09-20T20:00:00

Great, light weight

Sam G.

Originally posted at

2021-04-25T20:00:00

Heat to weight ratio is excellent

Jared

Originally posted at

2020-12-13T19:00:00

I haven't been in cold enough conditions to really test that aspect out, but so comfortable! I love it!

Ian M.

Originally posted at