Aztec Washer Company RF301BS-RD - Universal Retrofit Master Flash (3-1/4" - 10")

Aztec Washer RF301BS-RD is a size #3 universal retrofit flashing for large-diameter pipes and conduits when a standard slide-over boot won’t work. The split, wraparound design uses a crimp-to-seal seam and conforms to common metal roof panel profiles and roof pitches. Molded from UV- and ozone-resistant black EPDM, it trims cleanly on site and delivers a durable, weather-tight install.

Key Features: 

• Split, wraparound design with crimp-to-seal closure for true retrofit installs.
• Marked sizing rings for accurate, on-site trimming.
• Flexible EPDM base conforms to panel profiles and varying roof pitches.
• Simple five-step install: measure, trim, wrap, crimp, seal.

• Product line: Universal Retrofit Master Flash.
• Part number: RF301BS-RD.
• Size: #3.
• Material/color: EPDM, black.
• Pipe range: 3-1/4 in to 10 in (95–254 mm).
• Base size: 14-1/2 in (368 mm).
• Initial top opening: 3-1/4 in (95 mm).
• Installation method: Wraparound seam; crimp to seal; cut-to-fit sizing rings.
• Temperature guidance (EPDM, general): Continuous to ~212 °F (100 °C); intermittent to ~275 °F (135 °C).
• Typical use: Large roof or sidewall penetrations where slide-over boots won’t fit.

Q: What makes RF301BS-RD a retrofit flashing?
A: It is a split boot that wraps around existing pipes or conduit and crimps to seal, so you don’t need to disconnect lines.

Q: What pipe sizes does size #3 cover?
A: 3-1/4 in to 10 in (95–254 mm).

Q: What sealant should I use at the base?
A: Avoid petro-chemical-based sealants. Urethane or silicone caulking is typically recommended.

Q: When should I choose silicone instead of EPDM?
A: Use silicone where sustained temperatures exceed typical EPDM ranges; check equipment temperature specs to choose the correct compound.