Resealable, Archival Quality, Acid-Free, Anti-Static Crystal Clear Biaxially-Oriented Polypropylene - Perfect Protection For Your Collection! 10-3/4" Width x 10-3/8" Height + 1-1/2" Flap (or 273mm x 264mm + 38mm flap) - The Perfect Size! Fits Single, Double, & Gatefold 10" Records. Made by Long Term Record Supply Professionals - Sleeve Sellers for 40+ Years.