Are my window air and water leaks on my Bilt-Best windows due to bad weatherstrip?

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Biltbest Operation and Maintenance Parts for BiltBest Wood Windows
PDF Information on BILTBEST PATIO DOORS
Wood and Aluminum Metal-Clad Replacements and How To Videos
Special Function BiltBest Windows / Round-Tops / Awning Windows / Double-Hung Windows | Parts
BiltBest Window Replacement Screens
BiltBest Double-Hung Window Balances and Jambliner Replacements