This handy double sided pop up 18% grey/white card simplifies the complex technical issues surrounding exposure and color correction when working in different lighting conditions.It provides a major benefit when working under pressure at events such as weddings or shows.Gray side: Reflectance 178%; Density 074for Max. deviation of reflectance: 2%for Max. error in exposure measurements: 1/8 of F-stopcolour:Black + gray + whiteMaterial:clothsize:30x30cmPackage Contents:1x Focusing BoardOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.