AddGrace 6 Pack Heavy Duty Floating Shelf Bracket Hidden Shelf Brackets Concealed Shelf Support for Floating Wood Shelves (Black) 6" : Amazon.ca: Tools & Home Improvement
Floating Shelf Brackets Blind Shelf Brackets 6 Inch - Heavy Duty Wall Shelf Brackets for Custom Wood Shelves, All Metal Black Hidden Shelf Supports with Hardware (6 Pack) : Amazon.ca: Tools & Home Improvement
shelving - Hidden/Floating Hardware for Solid Wood Alcove Shelves? - Home Improvement Stack Exchange