The tz can convert from a day pack of about 1800cu to 4000 for overnight trips. Has a ton of adjustment in the harness to fit all body types. has a separate meat shelf compartment, build in bow/rifle holder and a rain cover
The pp15 is a predator pack. Has build in seat pad with legs that pop out to be used as a back rest, has a detachable bag for electronic call. Have a bino harness that I will throw in with the purchase of one of these packs. Both packs in kryptek highlander and very quiet