This is a standard Besa cap designed to work with standard conduit. Its diameter is 7.5cm. It is also possible to use this without conduit, as per the installation diagram, available below, but the connections must be housed in a suitable insulted box.
For an additional charge, you can upgrade to a cup fixture. This is a strapped cup with a diameter of 10cm and depth of 2cm. This larger size allows you to house the wire connections within the rose itself. This is a more traditional way of installing domestic lighting as it requires no conduit or extra space in the ceiling cavity.
.Click below to see installation instructions for each option: