Poster Palooza 21x21 Contemporary Black Wood Picture Square Frame - UV Acrylic, Foam Board Backing, Hanging Hardware Included! This Wood Picture Frame has been built for images measuring 21x21 Inches. Overall dimensions 21.5625x21.5625 Inches. Moulding Width: 0.5625 Inches - Rabbet Depth: 3/8 Inches UV Resistant Frame Grade Acrylic Sheet & Foam Board Backing Included. Hanging Hardware included for vertical or horizontal display.