Button 4-hole round | A4 | M8217

A cleat, also known as a bollard, 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.

TECHNICAL SPECIFICATIONS

• Product type: Cleat / bollard

• Material grade: Stainless steel A4 / AISI 316

• Surface treatment: Untreated – natural 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 anchoring devices for lines, ropes, and hawsers, but their design differs slightly:

• Cleat: Features a T-shaped or two-armed profile where the line is locked quickly and securely by being wrapped in a figure-eight pattern (cleat hitch). Ideal for mooring recreational boats, handling sheets and halyards, and securing lines on decks, docks, and masts.

• Bollard: Often consists of one or two vertical posts/cylinders (sometimes with a crossbar) designed to withstand high pulling 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 grueling 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 stress: Moorings are subjected to continuous jerking from waves, wind, and currents. 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 produce rust stains that discolor plastic decks, wooden docks, or mooring lines.

What should be considered regarding installation and choice of screws for an A4 cleat?

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

1. Correct screw grade: Always use acid-proof A4 screws for installation. Never mix materials (e.g., electro-galvanized or A2 screws) as this creates galvanic cells that will quickly break down the attachment.

2. Through-bolts and backing plates: For maximum strength on a deck or thin surface, the cleat should be fastened with through-bolts with M-threads (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.