This is a silicone seal that is used to hold the window in the frame. This is installed after the glass is in the frame. Clearview 10 for vintage Hehr fixed windows. Note to Airstream owners, this was used primarily on 1958-1960 Airstreams. Please check the outer sill of your window to make sure it has 10xx printed or stamped on it.
Price is per foot. The longest length in one piece is 24'