Each 47mm Adams suction cup is rated to hold 3 pounds (1.36kgs) in weight.
Adams 47mm diameter suction cup with long neck and gripper nubs or barbs, can be pushed into a drilled hole board of a 3mm thickness and the protruding 4 x 1mm nubs around the long neck circumference will ease back out and grip from behind. (see technical drawing image for dimensions).
It is ideal for poster boards where a quick fixing is preferred to a clear screw or brass nut.
This suction cup can also be pushed into a drilled section of a material. The nubs will act as a tight fit against the hole edge.