What's 'Lenticular'?
Simply speaking it is a series of lenses that allow you to view something from multiple angles and see different images. In this case it is used on this magnet to let you see two different images depending on the angle that you look at it from. The images switch between a Richard O'Brien's Rocky Horror Show colour logo and a black and white concentric rings version.

80mm x 58mm, magnetic.

Available at the show. £7.50