I have discovered that the Calculating Edge field case for the Pioneer series works great with the new HP 33S! Unbelievable as it may seem, my HP 33S fits snuggly inside the hard leather case, like my HP 67 did in its field case. I bought the Calculating Edge case for my HP 17Bii, but it bounced around in it like my HP 41CV did in my HP 35 field case. After awhile my HP 41CV's keys were significantly eroded due to all the chafing. I didn't want that to happen to my near production end HP 17Bii, so I didn't use the case until I happen to try it with my new HP 33S. Perfect!