We Ship Worldwide! | FREE SHIPPING! for US Continental orders over $99. Click for details.

Order Status Login 1-888-756-8883 Contact Us

Shopping Cart

Your cart is currently empty.

FREE SHIPPING! for US Continental orders over $99
click for details

Harken's MKIV, Ocean, Underdeck & Small Boat Furler


Harken is a renowned brand in the sailing and marine industry, specializing in high-quality sailing hardware and equipment. Known for its innovation and precision engineering, Harken produces a wide range of products, including winches, blocks, furling systems, and deck hardware. With a strong reputation for durability and performance, Harken products are trusted by sailors, racers, and boating enthusiasts worldwide to enhance their sailing experience. The brand's commitment to excellence has made Harken a leader in sailing technology, providing solutions that optimize sail handling, control, and overall sailing efficiency. Once we understand the concept that Harken represents and generates as a brand, we can talk about three products that stand out in the brand: Harken's MKIV, Ocean Underdeck & Small Boat Furler.

1. MKIV and Ocean Furler:

  • MKIV Furler: The Harken MKIV Furler is a series of roller furling systems designed for smaller to mid-sized sailing boats. It's designed to help sailors easily furl and unfurl their headsails (genoas and jibs) by turning a furling line or an electric winch. The MKIV Furler typically consists of a drum at the base of the forestay, which holds the furling line, and a swiveling top unit that attaches to the sail's tack. When the furling line is tightened, it wraps the sail around the forestay, effectively reducing the sail's area and making it easier to manage in changing wind conditions. The MKIV Furler is known for its reliability, ease of installation, and smooth operation.
  • MKIV Ocean Furler: The Harken MKIV Ocean Furler is a more heavy-duty version of the MKIV Furler, designed to handle the demands of larger sailboats and more challenging offshore conditions. It offers enhanced durability and strength to withstand the increased loads and stresses encountered during extended ocean passages. The MKIV Ocean Furler typically incorporates features like larger diameter extrusions, heavy-duty bearings, and other robust components to ensure reliable performance in harsh environments.

What are the differences between Harken’s MKIV and MKIV Ocean Furlers?

Both are designed for longevity and ease of use, but the MKIV has additional features that make it more suitable for performance cruising and racing.

Differences MKIV MKIV Ocean
Foils Aerodynamic foil profil. Double grooves for faster hoists, douses, and sail changes Single groove, round profile for easy rolling. Pass headstay wire and marine eye through foils. Cut top foil to fit. Bottom foil adjusts to fine-tune unit length
Halyard and Tack Swivels Indepent swivels for improved sail shape Fixed swivel
Drum Split drum removes for racing One-piece fixed drum, spool, and guard
Line Line is included Line is not included

2. Underdeck Furler:

An Ocean Underdeck Furler is a type of furling system designed primarily for larger sailboats. Unlike traditional above-deck furlers, an underdeck furler is installed below the deck of the sailboat. This design choice results in a cleaner deck layout by keeping the furling drum and mechanism out of sight, enhancing both the aesthetic appeal and the functionality of the sailboat. Ocean underdeck furlers are engineered to handle the demands of larger sails and typically come with features such as sturdy construction, efficient torque transmission, and reduced windage, which can be advantageous for performance-oriented sailing.

3. Small Boat Furler:

A Small Boat Furler is a compact and lightweight furling system designed for smaller sailboats, such as dinghies, daysailers, and other small craft. These furlers are usually installed above the deck and are tailored to handle the specific needs of smaller sail areas. Small boat furlers prioritize simplicity and ease of use, allowing sailors to quickly deploy and furl their sails even with limited crew or when sailing single-handedly. While they may have less complex control systems compared to larger furlers, small boat furlers are designed to withstand the conditions commonly encountered in smaller sailing vessels

Benefits between Harken’s MKIV, Ocean Underdeck & Small Boat Furlers.

Benefit  MKIV & Ocean Furler
 Underdeck Furler Small Boat Furler
Clean Deck Layout Some models offer above-deck installation, providing a cleaner deck layout. Below-deck installation keeps the deck clear of clutter. Provides a compact and unobtrusive deck setup.
Sail Control Options Manual and electric control options for ease of sail handling. Manual control, with potential for additional control mechanisms. Manual control for simple sail handling.
Windage and Aerodynamics Above-deck design may have higher windage compared to underdeck options. Below-deck design reduces windage and may improve aerodynamics. Compact design minimizes windage.
Load Capacity and Sail Area Suitable for medium to large sailboats, accommodating varying sail sizes. Designed for larger sailboats with corresponding sail area capacities. Tailored for small boats with smaller sail areas.
Ease of Installation Above-deck installation can be relatively straightforward. Below-deck installation may require more planning and effort. Simple installation suitable for small boat setups.
Durability and Performance High-quality materials and engineering contribute to durability and performance. Sturdy construction for reliable performance under load. Built to withstand the demands of small boat sailing.
Maintenance Requires periodic maintenance, including lubrication and inspection. Requires regular inspection and servicing to ensure optimal performance. Minimal maintenance requirements for straightforward use.
Below-Deck Design Not applicable, as MKIV furlers are generally above-deck. Below-deck design enhances the aesthetic and functionality of the deck. Not applicable, as small boat furlers are typically above-deck.
Control Line Diameter Compatibility Accommodates various control line diameters for different sail sizes. Designed to work with specific control line diameters and sail sizes. Tailored to accommodate control lines suitable for small boats.

Common Specifications between Harken’s MKIV, Ocean Underdeck & Small Boat Furlers

Specification MKIV  & Ocean Furler Underdeck Furler Small Boat Furler
Boat Size Compatibility Medium to Large Large Small
Installation Type Above Deck Below Deck Above Deck
Control Options Manual, Electric Manual, possibly Electric Manual
Bearing Type Ball Bearings Ball Bearings Ball Bearings
Material Stainless Steel, Aluminum Stainless Steel Stainless Steel
Load Capacity Varies by model Varies Varies
Durability High High Moderate to High
Maintenance Requirements Regular Lubrication, Inspection Periodic Inspection Periodic Inspection
Sailboat Type Various Larger Sailboats Small Boats
Below-Deck Dimensions N/A Required N/A


Don't forget to subscribe to our social media channels!