Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: Can smaller-size jars be used?
Document: As noted in other reviews, the spacing on the bars of the canning rack could be a bit closer. It's fine for larger jars, but causes smaller jelly jars to tip if they aren't balanced correctly between the bars. I'm going to try to make some sort of small adjustment to the rack to provide support for smaller jars since I do a lot of jelly jar size canning. Other than that, I'm happy with what I got for the price I paid.
Good Product, arrived quickly and in perfect condition. Used it for my first ever canning experience. It worked great. I found that the rack will not hold pint/half pint jars without them slipping through. Will have to purchase a different rack if canning in smaller jars.
I'm somewhat new to canning and was using a large stock pot. But because of this I was limited to the size of the jars I used. This fills the bill. I'm very glad I bought it
I love this, it is perfect for canning acid foods, no need for pressure canner. 21  1/2 qts. is rather large so if you do not have the room buy a smaller one. It was a good price and arrived on time in good condition. I have used it consistently since purchase.
A bit smaller than I anticipated, but I've used it several times and it works beautifully. I even had an overcook accident with it (my fault for getting distracted) and it cleaned up much more easily than my other pots. I will use it a lot and may see if I can get a larger version.
My previous Canner only had room for 7 jars and was crowded. This pot has room. I would recommend it to anyone who cans. Keep the other pot for smaller jobs.
The price seemed so low that I thought it would be really cheap, but it's nice. I've only used it once, but it was great. Easy to use, the rack did what it was advertised to do. I did use it on my flat top stove, even though it said not to. I didn't move it around at all, and I boiled water in a smaller pan and then poured it into the canner pot so it wouldn't take forever for the water to boil. Worked great.
Exactly as I expected. I needed one to be able to can quarts, and this more than fits the bill. Nice rack that has notches to hang from the top of the pot, so you don't have to reach down into the hot pot if you're doing smaller jars. Perfect!
I'm a first time canner, and this was nice and simple to use. The only caution is with smaller jars (1/2 pint) and smaller batches (less than 12) getting the jars positioned so they don't tip and are level in the basket can be tricky. All in all good product.
This canner is so much bigger than I imagined. The pot is bigger than most stove eyes. Luckily this wasn't a problem for me since I have a seperate electric burner that I used. The only draw back was that it did take a very long time for the liquid to come to a boil because of it's size. As long as you make time allowances it is not a problem. I made my first ever batch of canned pickles and it worked wonderfully. Definitely worth the money!
Answer: Yes, you just need to cover any size jar with at least an inch of water.  I've canned 1/2 pint to quart jars in this.