  Six 650 MHz high-power couplers will be integrated into the prototype High
Beta 650 MHz (HB650) cryomodule for the PIP-II project at Fermilab. The design
of the coupler is described, including design optimizations from the previous
generation. This paper then describes the coupler life-cycle, including
manufacturing, assembly, testing, conditioning, and the lessons learned at each
stage.
