Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: Does this come with a case? Can I buy one separately?
Document: so far i everything is good with the ear buds.i was amazed that they sent 3 diffident size ear squishy the little black piece that goes in your ear,there is a small med and large,only thing is they come off eazy so best to keep the ear buds in a small carrieing case not in your purse as they may get lost.the sound is great no problem behind ear, very flexible i was worried about it because i have glasses but no problems.
The positive side though - you get 6 replacement one of various sizes when you buy them - problem solved ! Great value
I tried these JVC and they are ok. They do not fly out of my ear like the Sony did, however, they still (regardless of the fitted tip) come lose to the point that they need to be put back in place regularly during a jog in order to hear. The sound canceling is not as good as what I found with the Sony earbud.
I bought these headphones for use while I run so the most important feature is that they fit comfortably and stay put during my run. They have met both of these requirements. I dont have to adjust them during my runs and they fit well and never feel like they are going to come out. If you are buying these for sound quality I would look elsewhere. There is very little bass with these headphones. For $12 it's not really surprising and for me that is really not much of a concern.
This a quality product at half the price I was going with the though that you get what you pay for and in this case I was very wrong I bought a very costly pair of polk headphones (similar  to these and the cost was $80.00 and they were on sale) tried them out and the sound was very bad sounded muffled.
(The default buds fit my ears well, but the headphones come equipped with three sizes, which are easily swapped out.) My old headphones had clips that rotated 360 degrees. They stayed in my ears well enough - except when I managed to catch or snag the cord on something. Then they'd jump right out of my ears, seemingly of their own accord. Not so with the new headphones - because the ear pieces are more rigid, the buds stay firmly in place.
These headphones are a very good value. They sound great, are comfortable, and stay put.They come with different size ear cushions.They fit "in the ear" and have solid bass. They do a good job of blocking external sound and have a good, overall well-rounded solid sound. They are slightly weak on the very high end definition, but not too bad.I recommend these for anyone who needs great over the ear, sound blocking headphones at a fair price.
I owned these a while ago and decided to buy them again since they were great. They deliver great sound and are comfortable.
They sound pretty good, and for their price, are champion performers. The cord is about the right length.Maybe I should buy a few more of them to serve as backups?
These are a very good deal. I was pleasantly surprised with these. Thought they might be just o.k. because they were not expensive. They are very comfortable and have very good sound. Would definitely buy them again. Worth the price
Answer: Don't come with a case, don't know about buying one separately