This Rubbermaid stack cooker is the older style melamine one for conventional oven up to 400 degrees or microwave.
It is heavier and thicker like Littonware or ultra 21.
It is used.
Has a chip on the flat lid cover part, see pics.
Has stains inside 3 quart bowl and 1 quart bowl.
This item contains 4 pieces:
One quart bowl
Three quart bowl
Colander bowl
And flat grill cover lid.
All are used but still usable.