This light cover fits round 1976 and 1977 Airstream interior lights.

Diameter at base is 8-3/4". The depth from the mounting surface for the switch to the base is 1-1/4". The narrowest internal depth is 7/8" from the base.

This is a NOS cover that is ivory in color rather than a lighter off-white that was available in recent years.  The plastic is in excellent new condition.

Original AS PN 200039 is no longer made.