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Dangerfield J Tool Through Door opening tool
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Dangerfield 'J-Tool' Reach-Through Door Thumbturn Opening Tool

  • 7 reviews  | 

  • £ 19.99 £ 23.99
    £ 23.99 Inc. Vat
  • Save £ 3.01 Save 0.0 Was £ 23.00* Was £ 27.60*
  • In Stock

Want it delivered by Tomorrow 24 Mar? Order within the next 0 hours, 44 minutes and choose [Next Day shipping] at checkout. Details. Priority Shipping available for all orders

Beginners Lockpick Guide included with all pick sets Lockpick Guide included with all pick sets

Dangerfield J-Tool: Reach-Through Door Thumbturn Opening Tool A MUST-HAVE for any WORKING LOCKSMITH Watch VIDEO at b... more

Dangerfield J-Tool: Reach-Through Door Thumbturn Opening Tool


Watch VIDEO at bottom of page.

The J-Tool works by exploiting the tiny gap between double doors (the type you'll see on commercial buildings) therefore allowing you to activate the interior thumbturn lock and gain NON-DESTRUCTIVE ENTRY quickly, easily, and with no mess or hassle.

With a little understanding and practice, you'll be able to use this tool in a matter of seconds.

The handle is comprised of two sections. The red part doesn't move, allowing you to insert the tool between the doors, and turn the 'u-shape' into position to engage the thumbturn part of the lock in the interior.

The shorter, black section of the handle is what engages the turning part of the tool, so once it's in position, you simply turn the lower, black part of the handle and rotate the tool, causing the thumbturn to unlock the door.

How to use:

  • Insert the 'U-Shaped' part through the gap between the doors
  • Turn secondary handle part to line up 'grabbing part' with thumbturn
  • Turn Primary handle part to turn 'grabbing part' to turn the thumbturn
  • The door is open


Occasionally, where there's not enough room to insert the tool, you can insert an inflatable AIR-WEDGE like one of THESE and create the tiny gap required for easy insertion. Having an air-wedge alongside this tool will make it even more effective and is recommended - but not always essential. They're handy to have in your kit-bag for many other reasons too.

The J-Tool also works on security grates and grilles. This tool is especially useful for first responders and of course, locksmiths, to avoid destructive entry on commercial doors, and allow for rapid entry.

See the J-Tool working in this VIDEO:

Order Processing:

Orders will be processed the same working day before 1pm, or the next working day from when payment has cleared. You will receive an email receipt once dispatched.

UK Delivery Information:

We offer Free UK Delivery as standard. Your order will be sent absolutely free via Royal Mail - and generally will be with you within 3 - 5 working days.

Get Priority Delivery to expedite your order processing and dispatch.

One-Day Delivery is available which speeds up delivery to 1 day after processing. Please ensure your order in in BEFORE 3 o'clock

We also offer a Signed 1- day Service for important packages - this functions in the same way as the One-Day service, but with extra signing security.

International Delivery Information:

For European orders with standard delivery - you should receive your items within 4 - 8 working days - shipping upgrades are available. 

For USA/Canada orders with standard delivery - you should receive your items within 5 - 12 working days - shipping upgrades are available.

For everyone else in the world  - we generally expect your orders to arrive between 7 - 14 working days. However, please allow up to 21 working days from day of dispatch.

We know you want your picks immediately. We routinely sell quality lock picks at hugely reduced prices and in great quantities. We sometimes even whip our staff to keep them working all through the night. Your orders are coming to you as soon as humanly possible! If you want a chat about some tools or ideas, or are thinking about making an order and aren't sure, drop us a line at and I'll happily help.

Conditions of Sale

Our products are available to responsible adults over the age of 18 years, for use in professional or hobby lock opening.

We reserve the right to cancel orders without notice.
UKBumpKeys cannot accept responsibility for loss or damage to any property caused by use of our tools, completing a purchase means you understand and agree to this.

International Orders

On your credit / debit card / payment statement, the charge will appear in your local bank currency. Our store will display the price in UK Pounds Sterling. We ship international orders every day. Please select the region correctly so correct taxes and postal rates are applied, any mistakes and you may end up paying extra. Sometimes a Customs Fee is charged, then the package is picked up from the post office, or when it is delivered - unfortunately, we cannot be responsible these fees - check on the internet for any potential fees that might be incurred. 

Return / Cancellation / Refund Policy

If you are unsatisfied you may return anything you purchase from UK Bump Keys for exchange or refund within 14 days of purchase as long as they are in new condition.  We will credit your credit/debit card, PayPal account within 30 day of the time we receive your return.

If you receive a defective product from us email  Please do not return defective products without authorization.  In most cases a new product will be sent to you or we will swap your defective item for a new one.

Making a return is simple.  Please contact us at to arrange this. If the item is not faulty you will be liable for return shipping costs and postage & Packaging fees incurred during dispatch.

Books and DVDs are not returnable unless defective.  You must notify us within 15 days of receipt.

Order cancellations are possible but not guaranteed.  If you request a cancelation and internally it is too late, please refuse the shipment and we will credit your card or issue a refund check when the items is returned to us.

Should you not not receive your order and we choose to send a replacement (which are considered on a case by case basis) we do not offer refunds on such resends.

Customers are liable for the return shipping cost of returned items. If the item is not faulty you will be liable for return shipping costs and postage & Packaging fees incurred during dispatch. All returns must be accompanied by a relevant RMA number (to be obtained from our support staff).

Orders are photographed and numbered before dispatch to prevent fraudulent faulty claims.


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