Instruction: Output yes if the supporting document can answer the given question. Otherwise, output no.

Input:
Question: there is a problem if space remains in the sack compression? that is, if I have spare space, well I can compress my sleeping bag? thanks!
Document: I previously ordered a Kelty compression sack and was not happy with, so bought one of these. They're great. Materials is strong and bag compresses very well. The medium and large compress to about the same size, so I ordered large. It fits a large bag in with room to spare before compressing and fits into my sleeping bag compartment. I recently bought two  Mountain Hardwear Pinole 20 mummy bags and they actually both fit into this huge sack.Highly recommend you get this if you need a compression sack.
This Compression bag has worked well so far. I've used it 4-5 times with only one problem...the draw string that closes the opening broke after just one use. It's not sturdy at all! Luckily, the draw string is not essential to the function of the compression sack, so it still works, but it's still a pain not being able to close the opening very tightly.Other than that, I have no complaints.
This was a good quality compression sack at an good price. The material is sturdy and the buckles are all of good quality. The stitching on the seams has been holding up well so far. I use it to compress my Eureka Wilderness sleeping bag. The original sack it came with broke almost immediately but this ALPS bag is working great. It has compressed down the bag to a reasonable size so it fits in my pack. I like it so much I bought a second one.
Not great for what I wanted (too big for clothes or two sleeping bags). No problem with the gear though, stuffed a tent and sleeping bag into one and had extra space. All my clothes couldn't fill the other if I were traveling for a week.Figure out what size you need before you buy, other than that, good buy.
I purchased the XL size to store a regular (non-mummy) synthetic sleeping bag. The XL size is 12&#34;x25&#34;, the large is 11&#34;x 23&#34;. I probably could have gotten away just using with the Large, but having a little extra space is no problem because it compresses down just the same.
I have not tried the small size for the compression sack, but I can definitely see it working for sizes even slightly smaller than my bag (if only through sheer force). Don't quote me on it, I'm only sure about the medium size compression bag and my sleeping bag.So as a conclusion, I'm probably going to buy a large compression bag, just to see if the size is going to affect the space in my backpack.
I recently purchased this ALPS Compression Stuff Sack in order to save some space in my backpack during my hikes. The sleeping bag that I purchased, a Coleman North Rim 0-Degree, is a bit bulky. The sleeping bag, when stuffed into the bag it came with, would take up a large portion of the main compartment in my backpack. After speaking to a few friends who are experienced backpackers I decided that this compression bag was the way to go.
This sure makes it more convient to store and haul my sleeping bag. This is a medium sack and it is the perfect size for a fluff filled bag. If you have a lightweight backpacking bag it will be too big, order a small.This is a well built sack from material to straps and clips. I would recommend compressing the sack before cinching the straps. If you try to compress while cinching the straps they may rip.
I use the medium to cram my mummy sleeping bag and a backpacking pillow together, compress them together a bit and it perfectly fills the space at the bottom of my 8yr old Gregory Z-pack.
I ordered a couple of these bags after receiving another compression bag made by Sea to Summit. These bags appear to me to be about half again stronger/more durable than Sea to Summit brand. Material seems thicker, the 'cups' on ends come down farther along the sides making the compression more uniform. The end cup is not sewn onto the open end of the stuff sack as the S-T-S brand is, but i did not find that to be of any significant problem in their use.
Answer: yes