5"x8" to 4" x 6-5/8" Starter Collar Reducer - 946-606 Regency MSRP: $131.00 946-606 is a 5"x8" to 4" x 6-5/8" Starter Collar Reducer used in applications where rigid pipe is used. Required for 770-994 (Duravent Rigid Pipe Adapter) Genuine OEM Part
