Bonas as in Oliver Bonas is a name. The surname Bonas is pronounced Bow-nas.
(The brand name came from the owner’s first name Oliver and his then girlfriend’s surname Bonas. The Oliver from Oliver Bonas was the man who was married to the woman who has an affair with Matt Hancock and was in those “very much not socially distanced” photos that forced Hancock to resign. I always felt sorry for Oliver from oliver Bonas, it’s bad enough finding out that your wife is cheating, but to find out from seeing photo on the front pages of the newspapers of your wife with her lover, and then to find the person she’s chosen to cheat with was Matt Hancock must be so horrific.)