zangra says

This dimmer can be used to control incandescent light bulbs as well as 230V halogen light bulbs. This dimmer is for the building in insulating wall boxes.
Please note that the visible parts are made of duroplast ( strong white plastic) . Only the cover is made of porcelain.

Remarks

AC 230V 50Hz, 60W-600W, Ø 8,2cm, pressure alternation
Works well with junction box (Ø 70mm, depth: 60mm)

Technical description