Offset Window Locking Mechanisms by Maco

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  • Offset Window Locking Mechanisms by Maco
  • Offset Window Locking Mechanisms by Maco
  • Offset Window Locking Mechanisms by Maco
  • Maco Offset Window Locking Mechanism
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MACO offset mushroom bolt espagnolettes for outward opening double glazing windows incorporate all the benefits of safety and security expected of modern window technology in today´s environment.

Available with 20mm or 25mm backset (Click here if you are unsure how to measure the backset)

The width of the faceplate is 16mm

These are described by industry standard lengths, but the actual length may differ slightly. see diagram below for specific measurements.

  • 310mm    20 or 25mm backset, window lock / mechanism           (Actual length 290mm)
  • 400mm    20 or 25mm backset, window lock / mechanism           (Actual length 380mm)
  • 600mm    20 or 25mm backset, window lock / mechanism           (Actual length 580mm)

PLEASE NOTE: Due to postage contraints the 800mm, 1000mm and 1200mm can only be sent via courier and not through the normal mail.

Click here to go to the "longer lengths" page

  • 800mm    20 or 25mm backset, window lock / mechanism           (Actual length 780mm)
  • 1000mm  20 or 25mm backset, window lock / mechanism           (Actual length 980mm)
  • 1200mm  20 or 25mm backset, window lock / mechanism           (Actual length 1180mm)



Measuring the backset on a window espag mechanism:



Not sure what window lock you need? 


 Call us on 01204 652211 for free advice



Information from the manufacturer

Offset espagnolette bar designed for profiles without a eurogroove.


Profile related keeps with night vent position.


Adjustable mushroom cams.


19mm cam travel.


360 hours salt spray corrosion resistance.


Espag Lock Backset Measuring Guide







To Measure the backset on your window lock you need to measure from the middle of the spindle hole to the front of the face plate. Take a look at the picture below and the red arrows show you where to measure.


The holes that the Bolts go through are a set distance and are the same on ALL window locks (43mm).



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Additional Information

*Sizes over 800mm are available in the links below.
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21 Reviews

  • 5
    Excellent Advice

    Posted by Robin Byers on Jul 16, 2020

    Great advice from your team. Even though the part I needed was now discontinued, you found the perfect solution, which fits beautifully. Thanks for the great service.

  • 4
    Off set window locking mechanism

    Posted by Bob Baker on Oct 09, 2019

    The company web site is very good at identifying the part you need, the locking mechanism was not a direct replacement, I knew this when ordered, so required re- positioning of the window locking plates. Again I knew I would have to do this and whilst this was a bit fiddly the window now locks as it should. My only disappointment was finding the locking mechanism is not made from stainless steel but coated mild steel, how long before it starts to rust? Hence my 4 star rating. Note from Handles and Hinges: unfortunately the manufacturer do not offer a stainless steel option.

  • 5
    window locking system

    Posted by simon on Mar 23, 2018

    this is the first time I have used this company. Website very helpful and able to select correct mechanism for oldish window . Only adjustment was to move keepers out by a few mm's as the window was shutting too tightly. Will use again when needed

  • 5
    Outstanding service

    Posted by John Beveridge on Mar 20, 2018

    Very impressive organisation Good product well priced and delivered quickly Would recommend to anyone

  • 5
    window locking mechanism

    Posted by william ingram on Jan 04, 2018

    dont usually do this but excellent site good easy checkout delivery charge good and got here very quickly considering time of year well done

  • 5
    Window locking mechanism

    Posted by Fred on Jun 30, 2017

    Brilliant ! Easy to order - instructions on how to measure are comprhensive. Website simple to use. Does the job at a very good price. Delivery on time. I highly recommend this company. The best.

  • 4

    Posted by Unknown on Aug 26, 2015


  • 5
    Fantastic product

    Posted by Joan on Apr 28, 2015

    Our window locking mechanism had been sprained and worn, so needed replacing. No-where had the same mechanism as ours but handles and hinges have a very helpful site and very helpful staff and we were able to find one that with a little bit of adjustment, fitted perfectly. We are now able to close the window properly again, without having to call in the experts. Delivered in record time too. Thanks

  • 5
    Does the job

    Posted by E Jones on Nov 15, 2014

    This replaced the existing window mechanism. It works very well although I had to chisel the upvc to make the Chanel that it sits in as it was not wide enough. This is probably because of my old windows. Very good value for money.

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