WhiBal G7 White Balance Studio Card Best specs of any gray card product (a*&b* &lt; 0.5 from perfect neutral) Only WhiBal is precision measured to certify specs of each and every card shipped. Designed for perfect compatibility with Adobe Photoshop and Lightroom. Sturdy and virtually indestructible only .040" thick. Scratch, fade, and water resistant.. Complete with WhiBal Studio card and 6mil polybag case