A pack of 4 x 47mm diameter Adams suction cups with nubs.
This strong suction cup has a long neck with protruding nubs around it's circumference. It is ideal for heavier posters upto 3m-4mm in thickness where a quick fixing is preferred to a clear screw or brass nut. Suction cups with nubs are also useful when fixing the neck into a solid drilled object.
The suction cup can be pushed through a drilled hole (see technical drawing image for dimensions) and the nubs will spring back out to their original height to grip the back of the poster.
Each 47mm Adams suction cup has a weight loading of 3 pounds (1.36kgs).