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Oxford Magnum D-Lock

From £39.99
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Product Description

Sold Secure Gold Rating

£1,000 Anti-theft Guarantee

The Oxford Magnum D-lock provides the best level of security for your frame. It has been accredited Sold Secure Gold, the highest rating a lock can achieve. Sold Secure Gold is bike insurer friendly.

Oxford’s Magnum D-lock is 5-minute attack tested against sawing, drilling and bolt cutters. They are so confident of its quality that the Magnum comes with a £1,000 Anti-theft Guarantee (there is a registration free).

You can fix the Oxford D-lock comes with a carry bracket, so you can fix it to your frame rather than having to carry the lock in your pack or bag.

Key Features:

  • Sold Secure Gold rated
  • 5-minute attack tested
  • £1000 Anti-theft Guarantee (Requires registration fee)
  • 16mm thick alloy steel U-Bar
  • High tech pick-resistant locking system
  • 2 x keys, carry bracket and lock head dust cover
  • Dual use product! Comes with carry bracket for cycle use
  • Sizes: 170mm x 315mm, 170mm x 285mm

    Occasionally, without notice, manufacturers change product design and/or specifications.

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    D-Lock Guide


    D-Lock Guide


    For use in medium to high crime areas

    A D-Lock (also known as a U-Lock) is the most practical bike lock you can get for peace of mind when you’re at the shops or in work all day.

    D-Locks are ideal for bike security as they offer strong protection against a range of attacks. While some of these locks will be heavy, they are much more portable than a chain lock and far tougher than a cable lock. D Locks are very stiff meaning they’re easy to fit around your bike and a stationary object.

    Most D-Locks come in two parts. You have the shackle made of steel or hardened steel with a diameter up to 18mm. The crossbar contains the locking mechanism and you slide the shackle into the bar and turn the key to fix it in place.


    D-Lock Size

    A standard D-Lock will easily fit around your bike and normal bike racks. If you have a particularly wide framed bike you can get wider and longer shackles. Alternatively, there is also a range of mini D-Locks are that specifically for use just with a standard bike rack. You won’t be able to fit your bike around a lamppost with a mini.

    For security, it is best to get a D-Lock which will fit your frame and stationary object without leaving too much internal space. A common way for thieves to defeat your D-Lock is by slipping another object like a crowbar inside the shackle and leveraging with enough force to break it open.

    D-lock attached to a lamp post

    Shackle Diameter

    When choosing a D-Lock, the thicker the shackle diameter is, the more secure it is (especially against bolt cutters). However, the trade off is weight. Some very sturdy D-Locks can weigh over 2.5kg. One tip is to lock your bike high on the frame and off the ground to make it harder to use bolt cutters.

    Small diameter d-lock

    13mm & Under:

    Under 13mm shackles can be cropped with most standard bolt cutters while some determination.

    The quality of steel used in the shackle can increase the time this takes. Ideal for quick visits to the shops.

    Medium diameter d-lock

    13mm – 16mm:

    At this diameter it becomes much harder to crop a D-Lock with a standard bolt cutter.

    Good for locking to the bike rack outside the office.

    Large diameter d-lock

    16mm & Over:

    With a shackle this burly only the largest bolt cutter jaws with sustained effort with crack through.

    It’s unlikely a thief will have the time or tools to cut through. Great for locking your bike overnight.

    Locking Mechanism

    Deadbolt Locking

    Most D-Locks will now use a deadbolt locking mechanism. A deadbolt cannot be moved to the open position except by rotating the key.

    Look for a double deadbolt for enhanced security. This means there is a locking bolt on both sides of the crossbar. Locking the shackle on both entry points greatly improves twisting and cutting resistance. Even if a thief cuts through one end of the shackle, it’ll be much harder to twist the shackle out of position.

    Some brands even offer quadruple deadbolt systems which lock the shackle to the crossbar in four places for maximum resistance.

    D-lock being carried in a back pocket


    Lock Material

    Almost all D Lock shackles and locking mechanisms are built out of steel. However, some locks will be constructed from hardened steel. By tempering steel if becomes harder and less brittle making it much tougher to cut through.

    Some locks use tempered steel for improved strength

    Sold Secure Rated

    A great way to determine the quality of a bike lock is to see if it is Sold Secure Rated. This is a third party, UK independent rating system for bike locks.

    Lock illustration showing the 3rd highest security rating of Bronze

    Sold Secure Bronze

    Coverage: Up to £500

    Lock illustration showing the 2nd highest security rating of Silver

    Sold Secure Silver

    Coverage: Up to £1,000

    Lock illustration showing the highest security rating of Gold

    Sold Secure Gold

    Coverage: Over £1,000

    An approved lock is graded as Gold, Silver or Bronze. The rating is chosen by how long it takes to break the lock and the tools needed to break it. If you're planning on insuring your bike, many insurers will state you need a Sold Secure rated lock to make a successful claim.

    These values vary between insurance providers so check the terms and conditions of your provider.


    If you commute to work or use your bike daily, then having a mount to fix your lock to your bike frame is a great way to improve portability. Many brands will include easy to use frame mounts with their D-Locks but check the product description first.

    Frame Protection

    D-Locks with vinyl covers, moulded end caps and rubber coatings all ensure that your bike frame is safe from scratches and damage to your paintwork.

    Vinyl-coated Kryptonite lock

    Delivery & Guarantee

    UK Delivery Information

    We are committed to offering fast and free delivery, whether you're ordering bikes, accessories or clothing. Our standard delivery service is FREE in the UK, regardless of the size and on all orders over £20.

    Please note that bulky products and bikes shipped to outlying UK regions are excluded from free shipping.

    Please note that Pre-Order dates can sometimes change due to updated stock information.

    Click here for more UK and international delivery information.

    Returns & Warranty

    It's easy to return a product with our 365 day, hassle free returns. 

    We will give you a full refund or exchange on any item that is returned to us unused/unfitted, in a resaleable condition and in its original packaging (where possible).

    Please note: For hygiene reasons, we cannot accept returns of facemasks, undershorts or underwear if the item has been removed/unsealed from its original packaging.

    If your item develops a fault or arrives damaged, please contact us first so we can resolve the issue for you as quickly as possible.

    For more information please visit our Returns & Warranty page.