Button 4-hole round | A4 | M8217

A round cleat with 4 mounting holes (M8217) in A4 stainless steel is a robust and reliable component for mooring boats and securing lines, ropes, and hawsers. It is manufactured from high-quality acid-proof stainless steel to provide maximum durability and resistance to corrosion, even during prolonged exposure in demanding marine and industrial environments. Sold individually.

AREA OF USE

The cleat is used for mooring boats and for securing lines, ropes, halyards, and sheets on decks, docks, and masts. It is mounted with four screws or through-bolts in acid-proof A4 and is suitable for both pleasure craft and docks in salt and fresh water.

TECHNICAL SPECIFICATIONS

• Product type: Cleat / bollard

• Material quality: Stainless steel A4 / AISI 316

• Surface finish: Untreated – naturally polished stainless steel

FREQUENTLY ASKED QUESTIONS (FAQ)

What is the difference between a cleat and a bollard, and what are they used for?

Both cleats and bollards are fasteners for lines, ropes, and hawsers, but their design differs slightly:

• Cleat: Has a T-shaped or two-armed profile where the line is locked quickly and securely by being looped in figure-eights (cleating). Ideal for mooring pleasure craft, handling sheets and halyards, and securing lines on decks, docks, and masts.

• Bollard: Consists of one or two vertical posts/cylinders (sometimes with a crossbar) designed to handle high tensile forces from heavier moorings.

Both provide a reliable and quick attachment point where lines can easily be secured or released without the need for complex knots.

Why is acid-proof stainless steel A4 (AISI 316) a must for cleats and bollards?

Mooring hardware is exposed to some of the most stressful environments imaginable:

• Saltwater and marine climate: A4 steel (1.4401 / AISI 316) contains molybdenum, which provides complete protection against crevice and pitting corrosion in brackish water and harsh saltwater.

• High mechanical load: Moorings are affected by continuous jerking from waves, wind, and flowing water. Acid-proof A4 steel combines high tensile strength with toughness, which prevents fatigue cracks in the material.

• No discoloration: Unlike simpler metals or surface-treated steel, A4 does not cause rust stains that discolor plastic decks, wooden docks, or mooring lines.

What should be considered regarding installation and screw selection for an A4 cleat?

Since a cleat or bollard can be subjected to very high tensile forces, proper installation is crucial for safety:

1. Correct screw quality: Always use acid-proof A4 screws during installation. Never mix materials (e.g., electro-galvanized or A2 screws), as galvanic cells will form and quickly degrade the fastening.

2. Through-bolt and backing washer: For maximum strength on a deck or thin surface, the cleat should be fastened with through-bolts (e.g., DIN 603 or DIN 933 A4) and large fender washers (DIN 9021 A4) or a reinforcement plate on the underside to distribute the force.

3. Sealing for deck mounting: Use marine sealant (e.g., polyurethane or MS polymer) around the screw holes to prevent water from penetrating the deck core.