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What size RetroDrain is appropriate for your application?

Please note that these calculations are based on U.S. measurements and roofing practices, and may not be sufficient or applicable for use outside of North America.

Enter the Inside Diameter (I.D.) of the existing drain leader.

The following OlyFlow RetroDrain(s) are available for this size drain leader:


Please call Customer Service at 800.633.3800 or 413.789.0252 if you need additional assistance or to place your order.