What lamp does a 7-inch fitter shade fit?

It fits lamps whose holder takes a 7-inch fitter, the common size on student and piano lamps. Measure your lamp's fitter ring before buying; a 6-inch or 8-inch holder will not seat it.

How big is the shade?

It is 6 inches high with a 4-3/4 inch top opening and a 7-inch fitter. That is a small shade, sized for a desk or reading lamp rather than a floor lamp.

What are the blemishes on the neck?

The neck part has some small blemishes. They sit where the shade meets the fitter, so check how visible they will be once the shade is mounted.

Is it glass or plastic?

It is a ruby red glass shade in the student style. Glass gives a warmer, more even light than plastic but chips if knocked.

Can I use it on a floor lamp?

Only if the floor lamp takes a 7-inch fitter and can carry a 6-inch shade. Most floor lamps use larger holders, so measure first.

Does the red color change the light?

Yes. Red glass tints the light warm and dims it compared with a clear or white shade, which suits reading and ambient light but not tasks needing bright white light.