They are internal frame packs. I know some people are hesitant to try and load them that heavy but with a hind quarter, front quarter, both backstraps and tenderloins, plus my gun and 2 liters of water the pack held the load like a dream.
Here's a link to their site
J34 "Just One" Backpack
If you want to buy one talk to Ceylon at Deltaoutdoorsman.com I believe he's a sponsor on this forum and he had the best prices when i bought mine.