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Discover the reliability of the Lewmar Size 20 Ocean Series Hatch Flange Base, a cornerstone for any seaworthy vessel. Crafted to withstand harsh marine environments, this flange base ensures a secure, watertight seal on deck hatches. Its robust construction supports the demands of ocean cruising, providing effortless ventilation and natural light below deck without compromising structural integrity.
Ideal for boat owners seeking a precise fit and long-lasting durability, this component integrates seamlessly with Lewmar's Ocean Series hatches. The smoke grey acrylic offers subtle UV protection and a sleek aesthetic that complements modern yacht designs.
Designed to mount on flat surfaces with a tight tolerance of +/- 1mm, installation is straightforward and professional-grade. Use M6 or 1/4" fasteners at the hinge section for rock-solid attachment, and 5mm CSK screws (No.10 UNC or 2 BA) for the lower frame to achieve a flush, streamlined finish.
| Lower Frame | Acrylic Colour | Hatch Weight (lb) | Acrylic Window Thickness (in) |
|---|---|---|---|
| 1" Flange | Smoke Grey | 6.04 | 3/8 |
These measurements guarantee a custom-like fit for your deck. Always double-check your cut-out against these specs to avoid rework.
| Length X (in) | Width Y (in) | Height Z (in) | Radii R (in) | Hinge Length HX (in) |
|---|---|---|---|---|
| Hinge Width HY (in) | Cut-Out Length Flat X1 (in) | Cut-Out Width Flat Y1 (in) | Cut-Out Radii Flat R1 (in) | |
| 10 1/16 | 16 3/16 | 1 9/16 | 2 11/16 | 3/16 |
| 8 7/8 | 7 15/16 | 13 11/16 | 1 7/16 |
Before fitting, ensure your deck surface is impeccably flat within the 1mm tolerance—sand or plane as needed for optimal performance. Apply marine-grade sealant around the flange perimeter to prevent leaks during heavy seas. Torque fasteners evenly to avoid warping, and test the hatch operation immediately after install. Lewmar's design minimizes hardware exposure, reducing snag risks and enhancing safety on deck.
Beyond specs, this flange base delivers real-world advantages. The 3/8-inch thick smoke grey acrylic resists yellowing and crazing from prolonged sun exposure, keeping your cabin bright for years. At just over 6 pounds, it won't overload your deck structure. Perfect for ventilation hatches in cabins, heads, or galleys, it promotes airflow to combat moisture buildup—a common issue in marine settings.
Compared to generic alternatives, Lewmar's engineering shines in extreme conditions: think gale-force winds or tropical downpours. It's a smart upgrade for older boats or a direct OEM replacement for peace of mind.
Keep it performing like new with routine checks. Rinse salt residue with fresh water after every voyage, and inspect seals annually. Lubricate hinges sparingly with marine grease to ensure smooth action. Avoid abrasive cleaners on the acrylic to preserve clarity.
It fits flat surfaces with a maximum tolerance of +/- 1mm for a secure, leak-free mount.
Hinge section: M6 or 1/4". Lower frame: 5mm CSK screw (No.10 UNC or 2 BA).
Smoke grey acrylic with 3/8-inch thickness for durability and UV resistance.
Approximately 6.04 pounds, making it lightweight yet sturdy.
Cut-out length flat (X1): 7 15/16 in; width flat (Y1): 13 11/16 in; radii flat (R1): 1 7/16 in.
Yes, part of the Lewmar Ocean Series, it's built for demanding marine conditions.
Rinse with fresh water regularly and use non-abrasive cleaners to prevent hazing.
| Lower Frame (in) | Acrylic Colour | Hatch Weight (lb) | Acrylic Window Thickness (in) |
| 1" Flange | Smoke Grey | 6.04 | 3/8 |
Dimensions
| Length X (in) | Width Y (in) | Height Z (in) | Radii R (in) | Hinge Length HX (in) | Hinge Width HY (in) | Cut-Out Length Flat X1 (in) | Cut-Out Width Flat Y1 (in) | Cut-Out Radii Flat R1 (in) |
| 10 1.2 | 16 3.16 | 1 9/16 | 2 11/16 | 3/16 | 8 7/8 | 7 15/16 | 13 11/16 | 1 7/16 |
Ships within 48 hours · Estimated delivery Aug 11 - Aug 16
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