Dome Shaped plug made of 6 mm acrylic. The structure of the dome is made of hexagon and pentagons bolted at the vertex using a triangular shaped joint. The triangular joint is made of two layers. One layer is milled with a step slope to provide a base for 2 hexagons and one pentagon. The second layer have inclined pockets for the M5 nut to sit inside. As these pockets are inclined i had to write the G code by hand for these.