We’re pleased to officially announce the launch of our brand-new 40mm dynamic block range. Available in 32 variations, all made from high-strength, lightweight glass-loaded nylon and featuring Allen’s dynamic bearing technology. The result is a high-performance block range suitable for keelboats and dinghies.

The new 40mm dynamic block range has been developed over the last couple of years with a focus on the high-performance keelboat and dinghy market. It features new variations that provide wider possibilities for different systems.

Our dynamic bearing technology is a key factor in the frictionless performance you can expect from this new range and sets it apart from the competition.

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What is Allen’s dynamic bearing technology?

We use stainless steel ball bearings instead of plastic ones. Stainless steel balls roll more quickly and last longer when subjected to high working loads compared to plastic alternatives.

Pairing this with a stainless steel rail for the balls to roll on further reduces friction and improves reliability and performance over a longer period.

Admittedly, the use of stainless steel for our dynamic bearings results in a slightly heavier product. However, we believe that the increase in performance and reliability outweighs the weight difference.

To further reduce friction, we have encapsulated the ball bearings in a cage, this stops each of the bearings from rubbing against each other. The reduced friction in caged ball bearings leads to improved performance. With less friction, the bearings can operate more efficiently, requiring less energy to rotate. This results in smoother operation, reduced wear, and improved overall performance of the block.

Swivel Shackle Attachment

Double, triple, and quadruple sheave variations all come with a lockable swivel shackle attachment. The shackle can be locked in 90-degree orientations. Alternatively, remove the shackle lock and allow the block to rotate freely.

Adjustable Cleat Arms

Single, double and triple sheave options are available with aluminium ball-bearing cam cleats mounted via an adjustable arm. The arm can be adjusted to suit your sheeting angle by simply loosening the nut and bolt through the centre of the block, loosening the side plates and retightening everything at the required angle.

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Becket and Fiddle Options

All of our blocks feature a large central hole through the middle of the sheave, which can be used as a tying-off point (becket), however, for the new 40mm Dynamic block range we have decided to introduce new variations with a specific becket moulding. This will allow even more rigging options, as now both the central hole and becket can be used to tie around.

The new fiddle variations feature a 20mm dynamic bearing sheave. This ensures that any purchase systems run as smoothly as possible.

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Suitable applications

Where do we start? This new 40mm range is our most versatile yet and is ideal for use on sports boats, dinghies, and yachts. It all comes down to the load rather than the size of the boat. This new range features breaking loads of up to 1400KG. So, we believe we’ve got most control line applications covered!

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Technical Specifications

SKU Title Breaking Load kg Maximum Working Load kg Length mm Maximum Line Diameter mm Shackle Pin mm Weight g
A20401 SINGLE WITH SWIVEL HEAD 780 240 82 10 4 54
A20401S-2030 40 & 30MM LINKED SINGLES 780 140 108 8 – 65
A20401-77 SINGLE WITH 77 CLEAT 750 80 82 6 4 120
A20401B SINGLE WITH BECKET 780 240 98 10 4 58
A20401B-77 SINGLE WITH BECKET AND 77 CLEAT 780 80 98 6 4 123
A20401BF SINGLE WITH BECKET AND FIDDLE 780 240 125 10 4 73
A20401BF-77 SINGLE WITH BECKET, FIDDLE AND 77 CLEAT 780 80 125 6 4 139
A20401BFH SINGLE WITH BECKET, FIDDLE AND HOOK 540 240 153 6 4 92
A20401BFH-77 SINGLE WITH BECKET, FIDDLE, HOOK AND 77 CLEAT 540 80 153 6 4 171
A20401H SINGLE WITH HOOK 540 250 110 10 – 73
A20401HL HIGH LOAD SINGLE 780 360 82 10 4 75
A20401C SINGLE CHEEK 780 240 62 10 – 34
A20401CB SINGLE CHEEK WITH BECKET 780 240 73 10 – 42
A20401F SINGLE WITH FIDDLE 780 240 107 10 4 68
A20401F-77 SINGLE WITH FIDDLE AND 77 CLEAT 780 80 107 6 4 134
A20401FH SINGLE WITH FIDDLE AND HOOK 540 240 135 6 4 87
A20401FH-77 SINGLE WITH FIDDLE, HOOK AND 77 CLEAT 540 80 135 6 4 153
A20401SLZ SINGLE WITH LACING EYE AND SPRING 700 240 78 10 – 47
A20401SR SINGLE WITH REMOVABLE STRAP 700 240 64 10 – 42
A20401S SINGLE WITH STRAP 700 240 65 10 – 40
A20402 DOUBLE 1150 500 92 10 5 109
A20402B DOUBLE WITH BECKET 1150 500 109 10 5 113
A20403 TRIPLE 1400 750 92 10 5 161
A20403-77 TRIPLE WITH 77 CLEAT 1400 750 92 6 5 239
A20403B TRIPLE WITH BECKET 1400 750 109 10 5 165
A20403B-77 TRIPLE WITH BECKET AND 77 CLEAT 1400 750 109 6 5 242
A20404 QUAD 1400 750 82 10 5 213
A2040Tii SINGLE Tii-ON 800 180 58 10 – 34.5
A2040TiiHL HIGH LOAD SINGLE Tii-ON 800 340 58 10 – 40

The 40mm dynamic block range is now in stock and available to order. If you have any further technical questions please do not hesitate to contact our sales team – sales@allenbrothers.co.uk