Both are harness, backplate and wing type systems: The TransPac is a 'soft' plate using a semi rigid high-tech material and the TransPlate is fully rigid metal plate. With a properly adjusted harness, both are equally as stable. We are sometimes asked if the TransPac can have a plate "added"; the answer is no. While other brands do offer "hybrid" systems, because of the nature of the TransPac design combining hard and soft plates together wouldn't produce any benefit. The hybrid systems offered by other brands can best be thought of as a TransPlate with a lumbar backpad option.
We most often recommend the TransPac because it is always more comfortable and form fitting than the TransPlate. Even adding a lumbar backpad to the TransPlate will not make it as comfortable or form-fitting as the TransPac. If you want to add extra weight, choose the stainless steel TransPlate system. Most people diving double cylinders choose the TransPlate. Most people diving single cylinders choose the TransPac. Most people who dive drysuit exclusively choose TransPlate, most people who dive wetsuit exclusively choose TransPac.
