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Alphalock Halyard Locks - Simply the Best?

The Alphalock brand is a relative newcomer on the sailing hardware scene but its CEO, Eric Hall - founder of Hall Spars and inventor of their renowned Hall Autolocks - is anything but "the new kid on the block"! Eric has taken all his years' experience and channeled them into producing an ultra-simple, lightweight and adaptable halyard locking mechanism. sat down with Eric to discuss his new technology and he started by describing where the name came from. "I was throwing around a few ideas but then it just hit me: 'Alpha', which means 'dominant' or 'leader of the pack'........ which is exactly what we are aiming to be. It also gets you at the top of any alphabetical list, which is a bonus!"

External / hanging "Block Lock"

Engineered by Eric himself, the most notable feature of this all-Titanium lock is its utter simplicity. Two side plates, x4 bolts and a single moving part, called the "Flipper", which simply rotates in the case to lock and unlock the compact Titanium bullet.

As an external hanging block lock, the Alphalock is fixed to the mast with a lashing or strop and the halyard passes up through the lock and then either directly down to the deck or into a halyard sheave on the mast. You can refer to our previous blog article on external locks for more information on the operation of these trip-less locks.

Internal lock

The original Alphalock design was symmetrical in shape and used x2 rotating flippers, one on either side of the halyard/bullet. However, with a simple modification to the design; to one flat side and one flipper, it becomes a clever, modular design. The same body can be used as both an external, hanging "Block lock" or attached to the inside of the mast wall to become an internal halyard lock. All that is required is a simple backing plate and an additional x4 bolts for the lock to be easily mounted on the mast wall, below the halyard sheave. The lock body fits through the hole to allow the lock to be retro-fitted from the outside and the universal bullet is designed to fit over the halyard sheave.

Halyards vs Hoist lines

Another interesting feature is that the Alphalock is designed to be used with standard sized halyards. One of the stated benefits for many lock systems is the reduction in weight due to the use of small diameter hoist lines. The argument is that once on the lock, it takes all the sailing loads and you only need a strong enough line to take the weight of the sail, while it is being hoisted.

However, unless you have a lock which uses a trip line release mechanism to unlock the halyard, the sail needs to be hoisted to release, which is where it can get tricky. If you are trying to unlock a fully powered code zero or asymmetric with a small trip line, this can be quite a challenge and line breakages are not unknown. With a simple, reliable mechanism and full-sized halyards, the Alphalock provides a very robust solution which inspires confidence.


With only one moving part, wear on the flipper is the only likely periodic maintenance requirement. However, the lock can be disassembled in a matter of minutes and the flipper is small and relatively inexpensive, which means this product scores highly in terms of ease of repair and maintenance.

Flexible, modular design

The Alphalock standard range consists of 6 sizes based on Safe Working Load (SWL): 1.5, 3, 5, 6, 9 and 12 tons and designed to take maximum halyard diameters of 6, 8, 10, 12, 14 and 16mm respectively. At each size there is one body, one flipper, one bullet and the option of a backing plate for internal installation on a mast or boom. It is very rare when you can find a single product which can be used as an internal or external halyard lock and then it is just as valid as an internal/external reef lock or even a headsail tackline.

The same technology is also incorporated into a range of custom and semi-custom mainsail headboard locking mechanisms but this is way beyond the scope of this article. Suffice it to say, the mechanics of this system are totally scalable and whether it is a 5T or 50T SWL, the single flipper design remains the same.


It takes a lot of effort to design-in simplicity / flexibility and it has taken Eric Hall more years than he would care to admit, to create this innovative block design. Asked to sum up the advantages of the Alphalock, his succinct answer was in-keeping with the product: "hyper-simple, full sized halyards and years of lock experience."

If you would like to get more information on the Alphalock range you can do so here or if you have any questions or require further information on halyard locking systems please contact us: Lock systems on

Alphalock Halyard Locks - Simply the Best?


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