In case someone is looking for parts list and don't want a crash course in hose fitting thread standardfs:
Three-way Shower diverter:
Garden hose to shower pipe adapter:
Hose Bib Quick Connect Adapter for RO tubing:
Picture of this combination on my shower:
Three-way Shower diverter:
Garden hose to shower pipe adapter:
Hose Bib Quick Connect Adapter for RO tubing:
Picture of this combination on my shower: