C-310A aluminum basement insert - Monarch replacement with expander / adapter and dual pane glass.
Size: 31 x 12-3/16 + Expander = 12-5/8
Columbia Series C310A Aluminum basement window replacement insert with insulated glass.
Maintenance free, energy efficient.
Easy, 1 minute installation.
Requires no tools for installation; uses high tensile steel spring clips to secure the insert in the opening.
Expander allows for use in most concrete basement walls with poured-in-place steel buck frames.
Color: Mill Aluminum finish standard
The Monarch was slightly smaller than Columbia and the Expander is added to the bottom of insert
The expander creates a 5/8\" thick leg that fits into the Steel Buck Frame.
Fits in buck with 1/2 to 5/8 inch drop-down (see third image)
31 x 12-3/16 + Expander = 12-5/8
31 x 16-3/16 + Expander = 16-5/8
31 x 20-3/16 + Expander = 20-5/8
31 x 36-3/16 + Expander = 36-5/8 egress window
Note: Basement inserts with expanders are used with Steel Frames, Aluminum Frames do not need the adapter.
Priced and sold each.Resources:
Article: How to Replace Basement Window Inserts
Video: How to Replace Basement Window Inserts