The Columbia Series 400A vinyl basement window is an insert with insulated glass.
Expander allows for use in most Concrete Basement walls with poured in place steel buck frame.
Available in white vinyl only.
The Monarch is 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.
*NOTE: Custom sizes are available--call to order
Information page: How to choose a window + removal/installation guide
Information video: Basement Window Replacement