Bestway Backflow
Ontario Plumbing Code mandates that ALL Trap Seal Primers, connected to Potable Water Systems, SHALL have either a RP, PVB or Air Gap. Nothing else meets code.
Ref: OBC 7.6.2.2. (1), 7.6.2.3.(1) & CSA B64.10-11
Which method will you look for? TrapGap.com