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Shed Shackle - The Only Police-Approved Shed Security Anchor!

Shed Shackle installed in a wooden shedPolice Approval: The Shed Shackle has been awarded Police Preferred Specification status under the PCPI Secured-by-Design scheme. It is the only Police-approved shed wall anchor on the market.

The Pragmasis Shed Shackle improves security for wooden sheds and a variant extends the same principle to metal sheds/bike stores.

Thefts from sheds have become more and more frequent and the options for improving your shed security have been either expensive, impractical, or both. Until now!

The Shed Shackle reinforces a large area of the wall of the shed so that a thief would have to saw or smash a huge section, making a lot of noise and taking a lot of time. (And even then, this would leave a large metal/wooden contraption still secured to your bicycle/etc!)

Unlike a conventional ground anchor, the Shed Shackle doesn't require a heavy concrete floor to the shed and actually improves the strength of the shed wall - your shed becomes steel reinforced!

Customer Comment: "You might like to know that we recently had our shed broken into with one bike stolen. However, the two bikes we had secured to the Shed Shackle were not touched!! So we have been asked by our residents to order another!! We all think the Shed Shackle is fab!!"

If you have high value items in need of protection, a good concrete floor with a Torc Ground Anchor may give you better security, at a higher price, but if a 100mm+ thickness concrete floor is unrealistic or if a floor-mounted anchor will be too awkward to use regularly or if the overall cost would be prohibitive, a Shed Shackle can offer a pragmatic and easy-to-use alternative that is still very likely to deter the thief.

Now Manufactured in Black: A recent introduction is the Black Shed Shackle. The Black Shed Shackle has identical dimensions and fixings: The only difference is the colour!


The following video gives a quick overview of the Shed Shackle:

The Shed Shackle has the following key features:

    Shed Shackle centre section in a wooden shed
  • Ideal for securing medium to high value bicycles and landscaping/gardening equipment
  • Designed for easy DIY installation in your shed
  • Reinforces a large area of the wooden or metal shed wall
  • Incorporates a side-brace to defeat twisting attacks
  • Upgraded Hardened Steel and special rivet-welded construction, with security shear nuts for attack resistance
  • Difficult and noisy to attack - Deters thieves
  • Modular design - You can arrange the bars to suit your own shed
  • Big enough to take heavy duty chains as well as D-locks and cable locks - The opening measures more than 50mm x 50mm (the sloping sides are a minimum of 50mm apart, widening to beyond 80mm). There is sufficient space to fit two of our Protector 11mm chains at once, or one 13mm and one 11mm at once
  • Sold Secure Approved (see below) and a European Registered Design
  • Police ACPO Secured-by-Design approved (suitable for credit points under the Code for Sustainable Homes initiative)
  • British design and manufacture - Support British industry!
  • Fitting kit includes all parts required and an appropriate drill bit
  • About 30 minutes to fit - Easy-to-follow and thoroughly illustrated instructions are included.
  • Variant available for use on metal sheds and bike stores!
  • DimensionsShed Shackle main metalwork, with a 300mm/12" ruler for scale

    The photo to the right shows the core metalwork, with a 12"/300mm ruler in between to give an idea of scale.

    The Shed Shackle is modular so you can fit it in many ways. It is made primarily from 30mm x 5mm thick steel bar, and the centre section (with the folded plate shackle) and the long extension bars are all 420mm long. The short side brace is 160mm long.

    In the usual configuration, with the centre section and both long extensions all in line (as shown in the photo towards the top of this page), the final assembly measures 1200mm long and approximately 174mm wide (the folded plate is 58mm wide, overhanging the 30mm-wide central bar, plus the length of the short side brace). The folded plate is made from 5mm thick steel sheet, hardened to resist sawing attacks etc. It will accommodate a Protector 16mm chain with ease, with the opening spanning a 50x50mm square, approximately. Feel free to ask us if you need any specific dimensional details.

    Shed Shackle Specification

    Click to download the Shed Shackle Specification (e.g. for trade customers). (Opens in a new window.)

    How do you Fit a Shed Shackle?

    The full fitting instructions are available for download on the How to Fit a Shed Shackle page.

    How Secure is the Shed Shackle?

    The Shed Shackle uses 5mm thick hardened steel in the critical central section. The original design used a 4mm thick central piece. This was very effective and it defeated many attempted thefts over several years, but it has been upgraded in recent production to increase the deterrent effect against thieves. This is in addition to the fact that it is typically very awkward for a thief to attack a Shed Shackle because it invariably has a bicycle, or something similar, leaning up against it and that obstructs access to the metalwork of the Shed Shackle, as well as to the fixings that secure it to the wall. We also now use CNC-machined heavy duty steel rivets, to our own design, to fix the hardened plate to the steel bar behind. This important joint is now welded from behind, for maximum strength. That joint is designed to achieve a very solid weld-through fixing to help it withstand extended attacks. Even though that joint is extremely strong, the central plate also gains more structural retention as a result of the inner pair of coach bolts also bolting through it. Years of evolution have improved the design of the Shed Shackle, maintaining the good reputation that it has always enjoyed.

    What's a shear nut? Why can't a thief simply use a spanner to undo the fixings?

    Shear Nut on a Coach Bolt, after ShearingShear nuts have special heads that comprise a conical smooth-surfaced part, which has the thread inside it, and a hexagonal bit on the top that allows you to use a conventional spanner to tighten them up. The key is that as they get tight, the hexagonal bit snaps off, leaving the anti-tamper fixing shown in the photo to the right. (We include push-on plastic caps to cover the bolt-ends, not shown in this photo.)

    Once the Shed Shackle is installed with all the nuts tight and all the hexagonal bits snapped off (sheared off), there is nothing left to put a spanner onto. Optionally, threadlock (not included in the kit) can be applied to the bolts to make it even harder for a thief that might attempt to grip hold of the smooth conical part that remains of the nut. (Threadlock is not normally necessary as the shear nuts alone are sufficiently tamper-proof, and there are eight bolts and shear nuts used to fix the Shed Shackle in position!) The outside of a wooden shed just exposes the dome-headed end of the coach bolts and we use anti-tamper bolt heads in the metal shed kit, so not only do the nuts have no remaining hexagonal part to put a spanner on, neither do the bolts.

    Police approved shed security Independent Approval:

    The Shed Shackle is Sold Secure approved to Domestic Silver standard. The Shed Shackle is also approved by the Police Secured-by-Design initiative - it is the only shed anchor with Police Preferred Specification.

    We have our Sold Secure and Secured-by-Design certificates available online so you can print your own copies, should you need them to prove certification for your insurance company etc.

    Fitting to a Metal Shed?

    The same Shed Shackle metalwork is just as useful and just as relevant for metal bike sheds/bike huts.

    Metal sheds tend to be flimsey structures with poor security, as illustrated on our page that gives advice on metal shed security.

    The Metal Shed Shackle can give a significant boost to the security without a huge amount of effort or cost.

    Another option for security in a metal shed/bike hut can be to install a proper ground anchor, such as the Torc ground anchor, but that requires the bike hut to be placed on a good quality concrete base, or for fresh concrete to be laid specifically for the purpose. That can give higher security, but it can be a lot more work and significantly more costly.Shed Shackle Centre Section in a wooden shed

    More details on the Shed Shackle for Wooden Sheds and for Metal Sheds

    The Shed Shackle is available in two variants that share the same core metalwork. The fittings are the only difference between these two options. The principle and main dimensions are identical, but the fitting procedure and the bolts used are completely different to cater for the different requirements of a wooden shed compared with a metal shed. These aspects are explained further, as follows:

    The full fitting instructions for both variants are available for download on the How to Fit a Shed Shackle page.

    We have another page that gives more details and suitability information on the Shed Shackle for wooden sheds, and also several photos of example installations. Similarly, we have more details on the Shed Shackle for metal sheds and other metal-walled structures such as bike huts and cycle stores.

    We also have more general guidance on security of wooden sheds and on security of metal sheds.

    Since the Shed Shackle is a modular product, it can be used in a variety of situations. If you have any queries that are not dealt with by the information provided here, feel free to contact us for clarification.

    The Shed Shackle is available on its own and in various Package Deals with large discounts. Reseller enquiries are welcome. Read our customer testimonials and also magazine reviews.


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