Home Decorators Collection 2 in. and 2.5 in. Cordless Faux Wood Blind Hidden Valance Clips (4-pieces) 10793478403103 - The Home Depot
2 1/2" Valance Clip for attaching a horizontal blind valance
LEVOLOR Trim+Go 2-Piece Horizontal Blind Clips in the Blind & Window Shade Parts department at Lowes.com
Amazon.com: 4pcs Valance Clips 3.5" Clear Vertical Blind Hidden Retainer Holder Installation Bracket with Built in Valance Outside Mount The headrail Size Measured 1.5"(38mm) in Top : Everything Else