Tii-on the best in marine hardware

Tii-on the best in marine hardware

Tii-on products are quickly becoming the go to choice for many hardware fittings. So, in this short article Allen list a few of their favourite products, as well as explain when and why Tii-on’s should be used. 

What is a Tii-on? 

Tii-on is Allen's brand name for products which require a soft attachment fitting (soft shackle/ rope shackle) or must be spliced or tied onto rope to be used correctly. 

Rope Development

Rope development plays a huge part of why Tii-on fittings are becoming so popular. Rope manufacturing technology has evolved over the years and as such there are now many different types of rope to choose from. Thanks to these developments by the rope manufacturer’s, rope is also now extremely strong. Gone are the days of needing 12mm + rope diameters for halyards and mainsheets.

3mm Dyneema® can be found with breaking loads of 1000+ Kg’s. Dyneema® is also 7 times lighter when compared to wire at the same strength. These developments mean wire running rigging which is commonly found in vang systems can be changed to softer, lighter, but just as strong, Dyneema®.

Why use Tii-on products? 

As sailing has progressed through the years we are seeing a bigger demand for stronger, lighter and more performance orientated hardware. So, naturally development took the path of removing the metal attachment points and metal shackles from blocks to reduce the weight and size. But then you are left with the problem of how to attach the product. Rope was the answer.

Rope is much easier to work with for the average sailor than wire. A simple knot can be tied around a block rather than having to bend and crimp a wire. Dyneema® can also be spliced to create continuous lines or loops, resulting in even more attachment options and uses. Splicing rope also removes the chances of snagging as there is no knots, crimps or anything protruding.

Now that Allen have created products designed specifically for attaching via rope or Tii-shackles it has allowed sailors to create much more efficient control systems, which are lighter, stronger and more compact than ever before.


Featuring their patented dynamic bearing technology of stainless-steel ball bearings running on a stainless-steel rails, the result is an unsurpassed performance under load when compared to others available on the market. The Tii-on block range is available in sheave sizes from 20mm up to 60mm and offers a large weight reduction when compared to the standard dynamic block range. What differentiates Allen Tii-on blocks from other soft-attach designs is the large stainless-steel ring at the head of the block. This ring is designed to stop the block from capsizing once spliced into a system as well as reducing the chance of the cheeks splitting apart. However, when splicing these blocks to an attachment that is wider than the block, a boom for example, it is still recommended that a cross splice is used to reduce the outwards load put onto the block.

When attaching a Tii-Block it is vital that you go through the loop in the head of the block, around the central axle and then back out through the loop at the top. The Tii-block range must be tied like this otherwise it will fail. The central axle is supposed to take the main load of the block. The central axle in the Tii-Block range is also designed to be used as a becket to give a wider range of cascade options.

High load thimbles 

High load thimbles  are perfect for splicing into a system and are generally used in applications where there is a high static load or at the end of a control line to adjust the angle of a sheet. 

High load thimbles can be used in either orientation, with the splice around the outside or through the middle.


Pad-Tii's are a great choice if you are looking to add an attachment point to a surface. They offer minimal protrusion yet are easy to thread rope around and give a strong, solid fixing point for any fitting.

There are two versions of the Pad-Tii but the fixed Tii-Bar version is the simplest option. Installation is easy as there are only two pieces; you simply push the threaded through-deck piece into the required fitting surface. The nut is then screwed on from the underside of the mounting surface, both pieces can then be tightened using a pair of circlip tools. For complete water tightness, it is recommended a small amount of sealant is used. 

Once the product is installed it leaves a smooth attachment point with minimal protrusion. The inside of the Pad-Tii features a domed shape to make feeding rope around the Tii-Bar extremely easy.

XHL Blocks

By combining the Allen patented dynamic bearing technology with a plain bearing peek washer Allen have created a bearing technology that has extreme dynamic performance even after being subject to static loads of up to 1250Kg. Coupled with CNC machined aluminium side cheeks and a precision turned stainless-steel sheave the range is perfect for use in vang cascades or halyard turning points where loads can be extremely high. These applications are also where you historically find a wire line, so instead Dyneema can be used to create simple cascade systems. The “ears” of the XHL range stop the block from capsizing and keep the load centred through the block.

Tii-on traveller cars

Allen traveller cars are CNC machined from extruded 6082 grade aluminium and feature recirculating ball bearings to give a durable, strong and smooth performance every time they slide. The 3 different sizes are available in a special Tii-on design, which allows for a much lighter and lower profile car. Fittings can be tied to the middle or side bars to allow for traveller car control lines to easily be installed.

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