Design transfer is to make sure that the design is correctly transferred into production specifications for manufacturing of the medical device. In fact, it is a confirmation that final product will be manufactured as per the intention of the design team.
Generally, it requires a review of the DMR (Device Master Record), which is a master design documentation for building the device. Review ensures that all the needed drawings are available and the production specifications are in sync with the design. It is a final check on any of the critical dimensions that are a must.