316 Stainless Steel Tube Base Flange – Round & Square Base

Why This Tube Base Flange Is the Right Choice

• True 316 marine stainless steel: Molybdenum-enhanced 316 SS delivers superior saltwater and chloride corrosion resistance compared to 304 SS or chrome-plated fittings — no rust, no pitting, no staining after years of offshore use.
• Mirror-polished finish: Electropolished to a bright mirror finish that resists fingerprints, cleans easily with a wipe, and looks premium on any vessel.
• Two base styles: Choose Round Base for a classic marine look on curved or flat surfaces, or Square Base for maximum footprint stability and load distribution on flat decks.
• 4 tube sizes: 22mm, 25mm, 30mm, and 32mm outer diameter — covers the full range of standard marine handrail and support tube sizes.
• 6.8mm mounting holes: Pre-drilled countersunk holes accept standard self-tapping screws for fast, secure installation on fiberglass, wood, or composite decks.
• Set screw locking: Side-mounted set screw clamps the tube firmly in the socket, preventing rotation or pull-out under lateral load.

Specifications by Tube Size (Round Base)

22mm Round Base

• Tube Inner Diameter (A): 22.5mm
• Base Diameter (B): 65mm
• Height (C): 42mm

25mm Round Base

• Tube Inner Diameter (A): 25.5mm
• Base Diameter (B): 70mm
• Height (C): 42.5mm

30mm Round Base

• Tube Inner Diameter (A): 30.5mm
• Base Diameter (B): 72mm
• Height (C): 43.1mm

32mm Round Base

• Tube Inner Diameter (A): 32mm
• Base Diameter (B): 75mm
• Height (C): 45mm

Common Specifications (All Models)

• Material: 316 marine-grade stainless steel
• Finish: Mirror polished
• Mounting Hole Diameter: 6.8mm (countersunk)
• Locking: Side set screw
• Base Styles: Round / Square
• Application: Boat handrails, bimini top uprights, canopy support tubes, dock railings

Perfect For

Motorboats, sailboats, yachts, pontoons, center consoles, and marina docks requiring permanent, corrosion-proof tube base mounting. Ideal for handrail installations, bimini top uprights, T-top support legs, and any vertical marine tube structure.