These mailers are a bit on the thin side. It wouldn't take much for a cd jewel case to rip through the bubble wrap and outside paper. You'll still need to add cardboard on each side the jewel case or risk a cracked jewel case in transit.
These are good sleeves but I must point out a comparison to the Scotch brand. My brother in California sent me a DVD plastic box (with a DVD in it.) I returned it to him in the same box but I had difficutly getting it to fit into the sleeve. Conclusion? The Staples brand are just a few hairs smaller on the inside. I still used it but it was bursting out at a couple of corners and I had to apply extra clear packing tape to make sure it didn't burst out of its stall. Overall a good product though.
Just the right size to pack a couple or even 3 jewel-boxed CDs. Some bubble-pack sizes are a pain to pack where you have to stuff them and it takes longer than it's worth. These are easy to use for mailing CDs and or DVDs.