Selkirk - 6" to 8" Ceiling / Cathedral Square Support Kit (UltimateONE)

SelkirkSKU: 6U1-CSSK

Sale price$737.36

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Size: 6-Inch
⛟ Estimated Delivery Date: Between and to all states excl. Alaska & Hawaii.

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Elevate your chimney system to new heights of performance with the Selkirk UltimateONE 6"-8" Ceiling/Cathedral Square Support Kit. This comprehensive kit is designed to provide robust support and termination components, ensuring your chimney system stands tall with confidence. Ideal for structures with flat or cathedral ceilings, it expertly navigates attic spaces and effortlessly penetrates roofs, guaranteeing top-notch performance and safety.

Crafted with meticulous attention to detail, this kit includes essential components like the Attic Insulation Shield (AIS), Ceiling/Cathedral Support - Square (SBCS), Round Top Termination Cap (CT), and Smoke Pipe Adapter (SPA). Each element seamlessly integrates into the UltimateONE Chimney system, providing a secure and reliable foundation for your home's heating solution.

UltimateONE's inner liner and outer casing boast a robust construction of all-welded 304 stainless steel, ensuring superior strength and corrosion resistance. Engineered with a web coupler design and 1" of Superwool insulation, it forms an impenetrable barrier, safeguarding your home against external elements. The system accommodates pipe expansion, eliminating the risk of cold air infiltration. With a latch-type locking band, installation is tool-free, quick, and consistently secure.


  • Superior Strength and Corrosion Resistance with 304 Stainless Steel
  • Continuous Protection with 1" Solid Pack Superwool Insulation
  • Adaptable Lengths for Effortless Installation
  • Eliminates Cold Air Infiltration, Enhancing Energy Efficiency
  • Versatile Compatibility with All Residential Fuels
  • Smart Choice Warranty Ensuring Long-lasting Reliability
  • Multiple Support Kits Available for Tailored Solutions


  • Engineered for Flat or Cathedral Ceilings and Roof Penetrations
  • Attic Insulation Shield (AIS) for Enhanced Safety
  • Square Ceiling/Cathedral Support (SBCS) for Robust Stability
  • Round Top Termination Cap (CT) for Sleek Aesthetics
  • Smoke Pipe Adapter (SPA) for Seamless Integration
  • Tool-Free Installation with Latch-Type Locking Band
  • Adjustable Lengths for Customized Fit


  • Diameter: 6" to 8"
  • Inner Liner Material: 304 Stainless Steel (316 Stainless available for 6")
  • Outer Wall Material: 304 Stainless Steel
  • Suitable for All Residential Fuels
  • 1" Solid Pack Superwool Insulation
  • Smart Choice Warranty on all Components
  • Product Code: 6U1-CSSK (6-Inch), 7U1-CSSK (7-Inch), 8U1-CSSK (8-Inch)
Product Code
Part No Size
6U1-CSSK 0842206 6-Inch
7U1-CSSK 0842207 7-Inch
8U1-CSSK 0842208 8-Inch

Warranty: Lifetime Limited Warranty

Refer to the Smart Choice Warranty for full warranty details.


About The Manufacturer:


Selkirk products set themselves apart from the competition with their proven quality, safety, ease of installation, and lasting performance.  Selkirk is one of the most trusted brands in the industry because we stand behind everything we do.  From assisting with product selection, providing education and installation assistance, to our industry-leading warranties, we ensure your success every step of the way.

      Order Confirmation:

      Upon placing your order, you will promptly receive an email confirmation. Subsequently, we will conduct a thorough inventory check to ensure all items are in stock and available for immediate shipment. If your order aligns with the advertised delivery timeframe, we will promptly process it for shipment to our warehouse. In cases where the expected delivery time extends beyond the advertised timeframe, we will reach out to you via email and/or phone for confirmation.

      Order Shipment:

      Within one business day of your item being shipped, you will receive an email confirmation containing a tracking number. If you do not receive tracking information within six business days of placing your order, please don't hesitate to get in touch with us for assistance.

      Estimated Time of Arrival:

      Our typical delivery timeframe ranges from 2 to 10 business days. Custom-made products generally require 3 to 5 weeks for delivery. If the expected delivery date for your order would fall outside of the advertised 2-10 business day time frame, our customer service team will contact you to ensure your agreement with the revised timeline.

      Covered Areas:

      Please note that all estimated delivery dates and shipping costs advertised on our website apply exclusively to the Contiguous United States. For inquiries regarding shipping to Hawaii or Alaska, kindly reach out to our customer service team. While we do not offer direct shipping to Canada, we are more than willing to ship your order to the freight carrier of your choice.


      It is very important that you inspect the packaging of your items when they arrive and check if you received all boxes listed on the delivery receipt. If you notice any damage or shortage of packages, you must make note of it on the bill of lading, take pictures, and refuse delivery. Your note should say "refused due to damage". You must also take photos of all sides of the box and send them to us within 2 days. If there are no damages visible before opening the box, you must note "subject to further inspection may contain concealed damage". If you notice any damage after receiving the delivery, do not throw the box away, and contact us with the photos. After we receive information from you about the refused delivery or concealed damage, we immediately initiate a claim with the shipping company or with the manufacturer. After the claim is fully processed, we ship all replacements at absolutely no cost to you.

      Cancellations & Refunds:

      We offer free order cancellations before the shipping label or Bill of Lading is generated, or prior to the commencement of production for custom orders. Please note that custom-made items are not eligible for refunds once production has begun. To be eligible for a return, the item must be unused and in its original condition, with all packaging intact and in perfect condition. Orders delivered outside of the United States are not eligible for refunds. If your order arrives damaged, please refer to the "Damages" section. Our refund policy extends for 30 days. If 30 days have elapsed since your purchase, regrettably, we cannot process a refund. Prior to returning an item, please contact us to discuss shipping details. All refunds will be credited to the original credit card or PayPal account used for the purchase, within two days of receiving the returned items at our warehouse.

      Please contact for any questions regarding shipping time.

      At Belleflame, we're committed to providing our customers with the best prices on the market. That's why we offer a 110% best price guarantee. If you find a better deal on the same product somewhere else, just let us know and we'll beat it by an additional 10%.

      We believe that shopping should be easy, convenient, and most importantly, affordable. That's why we work hard to bring you the lowest prices on the products you love. But if you do happen to find a better deal elsewhere, we'll go the extra mile to make sure you get the best deal possible.

      Here's how it works:

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      It's that simple! Our 110% best price guarantee ensures that you'll always get the best deal possible when you shop with us. So, why wait? Start shopping now and experience the difference of shopping with Belleflame.

      At Belleflame, we believe that shopping should be simple, stress-free, and most importantly, enjoyable. That's why we work hard to bring you the best products, prices, and customer service in the industry.

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