#6 PS, also known as Polystyrene, is commonly used in coffee cup lids, plastic cups, clamshell containers, coat hangers, medical disposables, some yoghurt and dairy containers. This material can be clear, glassy, rigid, brittle, opaque and semi tough.
Other common uses are in the form of Expanded Polystyrene which include foam packaging, packaging peanuts and styrofoam boxes. These are light weight, energy absorbing and heat insulating.
Don't be fooled by the triangular recycling label, #6 PS should be disposed of in your kerbside general waste bin.