Seamless Background paper is an artisan product made in batches. Thickness and weight of the final product varies slightly between colors and sizes due to differences in manufacturing processes and equipment.
Here are approximate industry standardized density measurements.
#1 Super White & #66 Pure White up to 107” width:
Paper Density: 163 GSM
All other colors in all sizes up to 107” width:
Paper Density: 145 GSM
Extra-Wide 140” width Seamless Paper; all colors:
Paper Density: 180 GSM